It’s simple. Go to Tachiyomi and create a backup. Then, in Mihon, during the first setup, it should give an option to restore backup. You can also resotre backup in Mihon settings, then go to extensions and (trust) the restored extensions.

It’s pretty much the same app at its core. So no need to change file names or formats. Everything should transfer.

I have a vita, too! If you own the Deck as well, which one is better? What kind of games do you play? I’m thinking of getting the OLED Deck for my Steam Indie library, but I still have a bunch of vita games to finish, so not sure if it’s worth it.