...
    push @regexes, $regex;
}

my $r = join '|', @regexes;
$r = qr/($r)/; # compile the regex
say "Regex is: $r"; # debug

my $string_to_search = "djflsbcdefgkgjdslkgjabfoéabcdefg";

if ($string_to_search =~ $r) {
    say "Found it ($1) at position ", $-[0];
}
# there is a useful magic variable @- (LAST_MATCH_START)
# check perldoc for it