Anglo-Saxon
Males                 Females                      
Arwold              Aebba                          
Bede                  Aelflaid            
Beornwine       Asthelberg                    
Caedmon          Aethelthryth  
Cerdic               Baldhild            
Ecgric                Bebba            
Egbert               Begu                
Gefmund          Cwenburg      
Hangist             Cyneburh            
Hewald             Cynwise          
Horsa                Eafe                  
Ingwold            Eanflaed        
Luidhard          Fara                  
Nothelm           Frigyth          
Octa                  Hilda                          
Osric                 Hildelith        
Raedwald         Osthryth        
Swaefred          Ricula            
Tunberht          Saethryth      
Wuffa                Verca  
Vowel & Consonant appearance (anglosaxon subgroup)
Vowel appearance (males vs female)
Sex   letter a   %     Letter e    %        letter i     %        letter o    %     letter u   %
M      10/20   50%   11/20    55%     6/20      30%      8/20    40%    3/20    15%
F       13/20   65%   14/20    70%     7/20      35%      1/20      5%    3/20    15%
Consonant appearance (males vs female)
Sex   letter b      %     Letter c    %      letter d   %     letter f     %        letter g      %
M       4/20       20%     5/20     25%     9/20   45%    3/20    15%       5/20       25%  
F        7/20       35%     5/20     25%     5/20   25%    5/20     25%      4/20       20%
Sex    letter h     %          letter j    %      letter k   %    letter l     %      letter m     %
M        6/20      30%        0/20     0%      0/20     0%    5/20    25%     3/20       15%
F         9/20      45%        0/20      0%     0/20     0%     8/20   40%      0/20       0%
Sex    letter n    %    letter p    %   letter q  %    letter r    %   letter s     %
M        7/20    35%    0/20     0%    0/20   0%   9/20    45%    4/20   20%
F         3/20    15%    0/20     0%    0/20   0%   10/20  50%    4/20   20%
Sex    letter t    %    letter v    %   letter w  %    letter x    %   letter y  %
M        5/20    25%   0/20    0%   7/20     35%   0/20   0%    0/20   0%
F         6/20    30%   1/20    5%   2/20     10%   0/20   0%   6/20   30%
Popular use
Potential female names
70% {E}
65% {A, e}
50% {R, a, e}, Rae, Aera, Are (Arku)
45% {H, r, a, e} Hera
40% {L, h, r, a, e} Helea, Hel
35% {B, i, l, h, r, a, e} Bilara, Aebba, Bebba
30% {T, y, b, i, l, h, r, a, e} Tybil, Aethelthryth
25% {C, d, f, t, y, b, i, l, h, r, a, e} Baldhild, Eafe, Fara, Hilda, Hildelith
20% {G, s, c, d, f, t, y, b, i, l, h, r, a, e} Shirley, Aelflaid, Asthelberg, Begu, Frigyth, Saethryth
15% {U, n, g, s, c, d, f, t, y, b, i, l, h, r, a, e} Sean, Banshee (Barns-hei), Cyneburh, Eanflaed, Ricula 
10% {W, u, n, g, s, c, d, f, t, y, b, i, l, h, r, a, e} Ngulwun, Cwenberg, Cynwise
5% {V, o, w, u, n, g, s, c, d, f, t, y, b, i, l, h, r, a, e} Connor, Dragon, Draco, Woden, Tybolt, Eve, Arwold, Osthryth, Verca
Potential male names
55% {E}   
50% {A, e}
45% {D, r, a, e} Drae, Rade, Edar, Erda, Erad, Eadr, Aedr, Aedar
40% {O, d, r, a, e} Daro, Odar
35% {N, w, o, d, r, a, e} Woden, Darren
30% {H, i, n, w, o, d, r, a, e} Odin, Hera
25% {C, g, l, t, h, i, n, w, o, d, r, a, e} Draco, Connor, Thingol, Dragon, Agon, Eldred, Thor, Otar, Arwold, Cerdic, Ecgric, Hewald, Ingwold, Nothelm, Octa, Raedwald 
20% {B, s, c, g, l, t, h, i, n, w, o, d, r, a, e} Banshee (Barns-hei), Sean, Bede, Beornwine, Egbert, Hangist, Horsa, Osric 
15% {U, f, m, b, s, c, g, l, t, h, i, n, w, o, d, r, a, e} William, Adolf, Gandalf, Hercules, Caedmon, Gefmund, Luidhard, Swaefred, Tunberht, Wuffa
Anglosaxon Group
Name length   4                  5                    6                 7                   8                  9        10                11        12
Male                  2/20 10%   3/20 15%   5/20 25%  5/20 25%    4/20 20%   1/20 5%  0/20  0%   0/20     0%      0/20  0%
Female             3/20  15%  4/20  20%  2/20  10%  2/20  10%  6/20 30%  2/20  10% 0/20   0%     0/20    0%  1/20  5%
 Irish
Males                 Females
Ailill                   Ailinn                  
Began                Aine              
Brendan           Aynia            
Bresal               Badb              
Cerbhall           Becuma        
Colum               Brigit            
Conchobhar    Cliodna                
Culann             Deirdre          
Cynyr               Emer            
Diarmaid        Etain              
Donnan           Ethnea          
Eoghan            Fand              
Erim                Fiona                
Ferghus          Grainne  
Gwiawn          Lethrenn      
Maelen            Liban            
Medr                Luchair              
Morfran          Medhbh        
Senan              Niamh                      
Uchdryd         Oenghus
Irish Group
Name length   4                 5                 6                 7                   8                9            10
Male            2/20 10%  4/20 20%  7/20 35% 4/20 20%  2/20 10%  9/20 45%  1/20  5%
Female       4/20  20%  5/20 25% 4/20  20%  5/20  25%   1/20 5%   0/20 0%  0/20  0%
Vowel & Consonant appearance (Irish subgroup)
Vowel appearance (males vs female)
Sex   letter a   %     Letter e    %        letter i     %        letter o    %     letter u   %
M      14/20   70%   10/20    50%     4/20      20%      5/20    25%    4/20    20%
F       14/20   70%   10/20    50%     11/20    55%      3/20    15%    2/20    10%
Consonant appearance (males vs female)
Sex   letter b      %     Letter c    %      letter d   %     letter f     %        letter g      %
M       5/20       25%     6/20     30%     5/20   25%    2/20    10%       3/20       15%  
F        5/20       25%     3/20     15%     5/20   25%    2/20     10%      3/20       15%
Sex    letter h     %          letter j    %      letter k   %    letter l     %      letter m     %
M        5/20      25%        0/20     0%      0/20     0%    5/20    25%     4/20       20%
F         6/20      30%        0/20      0%     0/20     0%     5/20   25%      4/20       20%
Sex    letter n    %       letter p    %   letter q  %    letter r    %       letter s     %
M        10/20    50%    0/20     0%    0/20   0%   10/20    50%    3/20       15%
F         13/20    65%    0/20     0%    0/20   0%   6/20       30%    1/20        5%
Sex    letter t    %     letter v    %   letter w  %    letter x    %     letter y  %
M        0/20    0%     0/20      0%   1/20     5%   0/20      0%    2/20    10%
F         4/20    20%   0/20      0%   0/20     0%   0/20      0%   1/20     10%
Popular use
Potential female names by popularity
70% {A}
65% {N, a} An, Anna
55% {I, n, a} Ain
50% {E, i, n, a} Aine
30% {H, r, e, i, n, a} Irina
25% {B, d, l, h, r, e, i, n, a} Ailinn, Badb, Deirdre, Liban
20% {M, t, b, d, l, h, r, e, i, n, a} Emer, Etain, Ethnea, Lethrenn, Medhbh, Niamh
15% {O, g, c, m, t, b, d, l, h, r, e, i, n, a} Connor, Draco, Brigit, Cliodna, Grainne
10% {U, f, y, o, g, c, m, t, b, d, l, h, r, e, i, n, a} Hel, Luna, Aynia, Becuma, Fand, Fiona, Luchair
5% {S, u, f, y, o, g, c, m, t, b, d, l, h, r, e, i, n, a} Sean, Banshee (Barns-hei) Oenghus
Potential male names by popularity of use
70% {A}   
50% {N, r, a, e} Arn, Nar, Nara, Ean, Ran, Ra, Ar, Enar
30% {C, n, r, a, e} Crane
25% {O, b, d, h, l, c, n, r, a, e} Hel, Connor, Nero, Brendan, Cerbhall, Conchobhar, Donnan
20% {I, u, m, o, b, d, h, l, c, n, r, a, e} Luna, Harlan, Ailill, Colum, Culann, Diarmaid, Erim, Maelen, Medr
15% {S, g, i, u, m, o, b, d, h, l, c, n, r, a, e} Bilara, Banshee (Barns-hei), Draco, Dragon, Sigmund, Sean, Began, Bresal, Eoghan, Senan
10% {F, y, s, g, i, u, m, o, b, d, h, l, c, n, r, a, e} Cynyr, Ferghus, Morfran, Uchdryd
5% {W, f, y, s, g, i, u, m, o, b, d, h, l, c, n, r, a, e} Gwiawn
Conclusions
Sean is more likely to be common amongst Anglo Saxon males than Irish, yet Connor is more likely to be an Irish or Anglo-saxon  name than Sean. In all likelyhood Sean originates with the Anglosaxons. These popularity trends can be down to the misdeeds associated with individuals, the source of a shared alphabet.
Aine is a standout name amongst Irish women. The need of a reduced character set for it to exist might mean it has an ancient origin as the name of the first Irish woman. Who is Aine?
Aebba & Bebba on the other hand are apparently Twins. Though not as popular amongst the Anglosaxons as Aine is to the Irish.