In the Devil is a Part-Timer, when Satan arrives in Tokyo, he's drained from passage into this world and discovers that there's no magic here. He uses up a good portion of it to produce sufficient money to get himself and his general a bare subsistence apartment. It's only later when he's able to tap into the fear of the people around him during an attack that he was able to achieve full power - only to have to use it up repairing the damage and removing the incident from people's minds.

There's another reverse isekai, [url=https://www.youtube.com/watch?v=_Ze98Hs4wjc]The Great Jahy Will Not Be Defeated![/url], where a demon gets deported to Tokyo with only a small power crystal. She looks like a small child, but the crystal allows her to temporarily assume an adult form so she can work in a neighborhood restaurant (or is it a bar?).

So I'm wondering if power-ups like crystals or holy vitamin B drinks is going to be a thing possible for some characters? Also, Emi brings a holy sword with her to Tokyo - are artifacts like that allowed?

I'm a little confused by the two character sheets as well. I'm assuming the second sheet is for Earth characters only and we don't have to fill out both?