Regarding your first question, are you referring to Izuku's harem in Izuku Alejo: The Paradox Hero or referring to Izuku's harem in Izuku Midoriya: The Multitype Hero?
Regarding your second question, I have never considered doing a Godzilla Izuku AU, but I have read stories featuring Izuku with Godzilla-like powers. While I am unsure if I would ever make a full story about a Godzilla Izuku AU, I can definitely include a story idea about that kind of AU in my Ideas for Future Stories book. What kind of story template do you think would work best for a Godzilla Izuku AU (Betrayed Izuku Neglected Izuku, Vigillante Izuku, Hero Izuku AU, Villain Izuku AU, etc)?