thanks ! I am also playing with "floating button (simi studio)" https://play.google.com/store/apps/details?id=com.simi.floatingbutton&hl=en&gl=US ... I like it because it has a lot of options ... like activate menu with a long press which works good with my old thick thumb ;) ...
If you want to run an app with a different account, you will need a duplicator app like island.
https://play.google.com/store/apps/details?id=com.oasisfeng.island&hl=en_US&gl=US