My long-term DM came up with a great way to trial run alternative IPs without going through a lengthy character creation and the associated challenges with learning a new system. Take your DnD Character and shunt them into a totally new IP for a one shot, fitting the new IP as appropriate to the character. Easier for human characters, less so for others.
So have Mictlan in 4 flavors:
Dungeons and Dragons One of the OG tabletop RPGs, this system combines high fantasy, magic, and adventure in world that has had nearly 50 years to be fleshed out. https://dnd.wizards.com/
7th Sea Pirates, Corsairs and Ships, oh my! Set in the golden age of piracy in off-brand Europe, you and your crew set sail for action, adventure and booty. https://www.chaosium.com/7th-sea/
Monster of the Week (Gonna date myself here) Have you wanted to star in Buffy the Vampire Slayer? Supernatural? Now you can. Investigate mysteries, hunt monsters, all set in the present day. https://www.evilhat.com/home/monster-of-the-week/