First build a list (i ain't smart), then use it

my @List = qw/ Mac Mc De /;
my @NAMES = map ucfirst, qw/ mcginley macgee develera/;

for my $name (@NAMES) {
    for my $match( grep {$name =~/^$_/} @List ) {
        warn $name;
        $name =~ s/^\Q$match\E(.*)$/$match.ucfirst($1)/e;
        warn $name;
    }
}
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The output from the above code I get is

Mcginley at - line 6.
McGinley at - line 8.
Macgee at - line 6.
MacGee at - line 8.
Develera at - line 6.
DeVelera at - line 8.