I’m sorry, but I do not have the time, experience or knowledge to set up custom ROMs in my device at the moment.

Manufacturer’s version of Android. I’ve logged in the apps with multiple Google accounts.

While I could consider using my browser instead of apps for all google related services, I don’t think outright removing the accounts from my phone since Google has mandated use of mobile verification (the one where they ask to choose the correct option from the three given number) and I don’t want to provide them a phone number for SMS verification. I fear I would be locked out of my Google accounts if I don’t have them signed in in my phone directly.

I tried checking Shelter, however it says it is best optimized for Pixel phones and grapheneOS (which I have neither of) and you already said sandboxing in Android sucks, thus it may not be beneficial to go through all that effort to setting up the separate profiles if it isn’t even going to work well.