Do the "main-sub" banks in different countries share information if one of them in non CRS country?

VTB bank. It’s a Russian bank. It also exists in Armenia. Russia is a CRS country, Armenia isn’t.

Will a VTB bank in Armenia share info with VTB in Russia if a russian citizen opens an account in VTB Armenia? I mean, any russian citizen who opens such an account. Not necessarily the russians those who live in Russia permanently – tax residents.

My guess is that it would be a violation of Armenian law for VTB Armenia to share information with VTB Russia, as it still has not signed on to CRS. BUT, it HAS signed on to The Convention On Mutual Administrative Asistance In Tax Matters, as of 2020. So if you are a Russian citizen, I’d say give Armenia a pass.