I would not mind having nothing but only cosmetics transferred (AC, SG tix used) to JP.
I could care less about my weapons, titles, meseta, and achievements being lost. At least restarting the game again in JP, you would start off looking decked out instead of recollecting cosmetics again. Heck, it might be even fun to learn how things in the JP version worked compared to the Global version counterpart in aspect of weapon building, the requirement of achievement titles, etc.
It would create a fun PSO2 experience that you accumulated in Global to how and why is JP version is different. It will create that happy medium for people who would like to play with JP peers. And you can experience the content that the others yearn for: deleted scenes, skipped anime collaborations, height restriction. It does suck that you have to re-earn titles, and build your weapon again but, at the very least, you have the best portion of your data from Global to JP anyways, phashion.
All the AC and SG cosmetics are pretty much the same from Global to JP. The only thing I can think of that is unique to Global to JP in terms of cosmetics is the Xbox emote, and the controller accessory. They have to accommodate that portion of the code to JP client or edit it out.
I don't mind starting over, I just want my cosmetics.