Hi.
The same settings will not sound the same in JUP-8 V3 and V4. Perhaps Arturia create a preset converter, but things have been changed so i think presets will have to be redone anuway to sound the same. I would like a preset converter anyway.
If you owned JUP-8 V3, then you can still use it alongside Jup-8 V4. Beside that you can try to copy the settings manually, and see which result that'll give you.