The only info on this is a job ad from November 2019 where it said the game "is now going into full production":
https://www.rpgsite.net/news/9790-fi...s-as-fake-news

Given that they only released Shadowbringers in July 2019, it seems entirely possible that they only started it quite recently, which would probably mean 2022 at the absolute earliest.

My guess is that FF7R Part 2 comes out first.