This makes perfectly sense on one hand. On the other hand, this misbehaviour appeared all of a sudden, that is, it did work one day and stopped working the next day. This was 1~2 weeks ago, and there was no Xiaomi/Android/MIUI nor an Evernote software update. Can't say for sure regarding Android System WebView, though.
After all, some combination of software components must have changed, which broke the Evernote camera access. No other installed app is facing this kind of problem.