Hi there.
I 100% get this is a new version and might be some tweaks to adjust. I appreciate the work the devs and everyone working on this project.
I did my save backup via Checkpoint, moved to PC, opened in Pkehex. The only thing I wanted to do was edit the nature of my Evee and started, I did, I rerolled the PID, the legality checker had the check-mark.
I imported the save via checkpoint, and in fact, I saw the new nature in-game(under the capture info), but, when I went to stats, the arrows which indicate the benefitial stat and the one hindered show the original arrows, so the name changed but not the actual stats.
I tested it further by using the same pokemon twice, one with the original nature and one with the modified one.
I evolved both pokemons to the same one, and leveled them once each and the stats are 100% the same.
Hopefully someone can give me advice.