I had the same issue (2 devices with separate logins) with arlo for over 1 year before they fixed it.
So seems not to be the most simple task.
With eufy I had to abandon it completely. Even with just one device, my phone being the only one it did not turn on nor off the cameras. Very unreliable so I just put the eufy cams I have (7 of them) in places that need survaillance all the time and just have them on at all times and then use 4 arlo for the spots heavy trafficed and therefore needs geo fencing not to drain battery to quick.
I wish I could schedule eufy to send or not send push aswell. To bad that is only on the camera setting and not in the security settings.