yeah! i opened the eshop and instead of going to the redownload section, i searched fire emblem in the actual store. since you already bought both you should be able to just install fe by itself instead of it doing fe + expansion pass. hopefully that makes sense!
(td;lr) do not reinstall the fe + expansion pass just look for the base game in the eshop and dl it by itself. when its done download the RELEASED dlc only instead of all at once.
if you need more help feel free to message me! if anything is wrong i apologize, my game still has an hour and 4 mins remaining... but it seems like this worked for many people!
p.s. my twitter is reolovebot and my ig is shinomiyakei, this was the max amount of posts i can make today so if u need help msg me there t___t