Twitch is so borked currently this is not possible using the script presented here. You would have to catch the mode commands and keep a list.

You would do that by the mode command. This will not be a real time process.

on 1:MODE:#mIRC:/notice $me $nick changed $chan mode to $1-


I capture the output of the mods command .mods for several functions, but that shows all mods not just the ones online