Dropping in to say I'm experiencing the same problem and asking Evernote team to solve this ASAP.
I updated to the lastest version on Windows (on the 8th of Nov 2020): Evernote 10.2.4 , for Windows. (NOTE: This is NOT a beta).
Still no preferences, still impossible to remove spell check, making the text unreadable. Can't even add words to the dictionary, there's nothing.
This is being a big issue, I hope it is solved soon, I'm experiencing this both in English and Italian.
I've attached a snapshot to show how obnoxious this is.