Sounds cool on paper, but it's just superpowered masturbation if the MC uses it to project someone for himself. He could use it in a MMF or MFF threesome, but for the latter he has options (see below) and for the former unless he really wants to project someone else, he could use duplication, instead.Cat can make more of herself. Iz (whose power we don't get ATM) can make ANYBODY.
Evelyn has proven willing to do anything to make MC happy. Georgia could easily be convinced (probably Amber, too, in the future), Tanya could be ordered. Just saying, if the MC needs to entice a woman using another woman, he's already got a lot of options and it'd be interesting to see who would be willing to turn down those girls.Isabella's power would let him make a projection of the person someone else most desires or anyone else he's aware of. Ignoring for a moment the creative fun you could have with love interests you're already with (Threesomes with Anna for everyone! Have sex with two Evelyns! Etc.), that could also be very useful for enticing someone new to share their power with him. Especially if that potential new person favors women over men.
Funny enough, I only see 'practical' applications for Isabella's power (assuming MC already has Cat's power). Like conjuring a projection to distract someone or something. Further, we know that duplicates carry the metagene, which means the MC should be able to use duplicates to gain powers. Something that can't be done with projections (unless, of course, MC can enhance the power). I very much look forward to the dev proving me wrong, though.