One way to replace is to use s///: 
use strict;
use warnings;

my $text;
while ( my $text = <DATA> ) {
    # match a word that contain 'ou' or #
    if ( $text =~ m/(ou)|(#)$/ ) {
        $text =~ s{[/\\]}{-}g;
        print $text;
    }
}

__DATA__
hello.world#
world\tour
Game.started

[download]

That replaces the \ and the / with -. You can add the rest.

UPDATE: added alternate delimiters in response to OP private msg.

In reply to Re: regex renaming by toolic
in thread regex renaming by ArifS

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