I moved over just my saves and had no issues. so I'm going to just have to add my mods in one by one and see if its any of those... I'll update if I find the one causing the issue.
I found the problem!!!! I was confused, because I had done a clean reinstall before and had the same issue. Like moving the folder, starting up a new game and copying my stuff to the newly created folder. Only this time I moved over just saves first and tried that- no issues. Then, I painstakingly went through ALL of my CC and mods (22.8 GB 😭) adding them all in one by one or in groups to see how the game ran. After that terrible process, I was so happy to have my game running smoothly that i stopped there, thinking the issue was a fluke. But today, I wanted to place a lot, opened my gallery and found nothing but the original maxis lots& households. So then I remembered I forgot to import my old tray folder. THIS IS THE ISSUE! As soon as I copied over my tray folder and started up the game (which took 3x longer than it had after my clean reinstall), everything was laggy. I could barely move my mouse this time. I never realized the tray could slow down the game so much, but if you think about it I have been saving all the pretty sims and pretty lots and houses I see since the game came out in 2014. That’s A LOT of data..but it’s only 65.7 MB so I never thought of it as a lot. Thanks for the help! And for others with the same issue I hope this fixes it for you too! So happy I can finally start playing with Realm of Magic, since my game was too slow to do so before now.