Some effects are broken on Studio mode when adjusted, so it's probably easier to find the effect's image from the game's folder and use an art app to edit it and put it on the character. I'm sure there was a folder in my phone's files called "com.lunime.gachaclub" or something similar, but I can't find it anymore.
It's obviously not because of some update, this game hasn't been updated for 2 DARN YEARS. And it's impossible to just take a screenshot of the effect and erase the background when it's partially transparent. Unless you're the god or goddess of editing. So where are are the game's folders and files? Can we actually see and use them, or is Gacha Club literally just an executable like Sunky the Game?