the android app he is using is android sdk showcase, and the software he is using to change camera feed is many cam and the emulator he is using is mumu player.
this looks excellent on video but not gonna work in real life , maybe u can bypass some third world country's small app which is probably made a dev team of 2 people. but big players like veriff has very advanced verification which, which inclues depth percption, virtual camera check, environment check and many more. which is next to impossible to do , you can do it just by trial and errror though I bet how advanced some ai tools are right now u can definetly find some way but this is not the one