the game only has some parts of menu in english, some guys here are working on some combed MTL, otherwise it's either learn moon runes, use a mtl tool or wait after the full release since the dev planned on making an eng translation but will probably use mtl too
Look for RpgMakerSaveEdit, I use that, it can change stats, give you items and activate variables and such, you can even unlock the full gallery but it's going to take a while since you have to manually click through each and every option (more than 1k) if you want that