actually I stumbled over this code from Brian d Foy, it shows a (well actually two) ways to parse the name the keyword \bWITH\b

use utf8;
use v5.32;
use open qw(:std :utf8);

no warnings qw(experimental::uniprop_wildcards);

use charnames qw();

my @letters = qw(a à á â ã ä å);

foreach my $letter ( @letters ) {
    my $name = charnames::viacode( ord $letter );
    say "$letter ($name):",
        $letter =~ m<\p{Name=/\bWITH\b/}>
        ?
        'Matched' : 'Missed';
    }
[download]

In the next step I want to speed this up by preparing the mapping list for all latin characters beforehand, like this I can use simple character classes in the regexes.

I was expecting to find a custom function which gives me these equivalent characters right away, probably prop_invmap of Unicode::UCD can be used for this.