Is it in a nups file extension? If so then in nups select ignore. If it’s still in a RAR file type then extract it.
I’m going to say no, since our cast is already set and we don’t have enough support slots to add any more characters to be playable, and switching an existing character to this class means that Astra or I will have to make more animations than we have to, which is a lot of work. It’s certainly something I’d like to see in other hacks, but we don’t have plans to add any.