This should be the last one. I already converted to the offline version and combed through every asset, so I'm confident there aren't any more. The game's wiki on Fandom doesn't have any more in their comic gallery, either.

Time is running out. If you have a Tales of the Rays account, you have until October 22nd, 12:00 AM JPT to convert to the offline version. You can see what features should be available here. I haven't seen anything about battles in there, but I've confirmed they are still available in the offline version.