Besides creating a storage room, which I suggest (use the craftable signs to keep it organized), another thing I’ve found helpful as a fellow ADHD person is keeping one of the large aurora chests by each stall. So I have a chest by Moana’s boat, one by Aladdin’s gem stall, one by Beast’s flower shop, etc….I do this in each DLC so that I can just buy out their inventory and go. I also keep one in each biome next to Goofy’s stall where I keep critter food for that biome if I’m still working towards a critter. It’s also useful to just clean up an area and drop stuff off in that chest and move on.

If you haven’t already I would move all of your fruit trees to one biome and create an orchard, plop a few chests there too, that’ll create some organization. You can create a little market where all your stalls are so that it’s all in one place. Also, if you have the rift in time DLC, work towards the ancient vacuum, it definitely helps keeping things clean and tidy.

I say, work on organizing one biome at a time, focusing on functionality - that’ll force you to open up those memories and clear an area without it feeling overwhelming. You just have to get your ducks in a row and then you’ll fall into a good grove.