Fake Traveler is another GPS spoofer that was recommended online, since you say MockGPS didn’t work consistently for you.

There is an option in the developer options to enable a fake location app.

https://github.com/lilstiffy/MockGps

Ideally you would want to remove your carrier sim. your carrier will know you are in a different country (roaming), and use a good VPN

I use mullvad VPN and that spoofs my GPS and location.

I use Lineage on my current phone with no google apps and dont use a fake location app.

If you are using a default, we love google phone, I am not sure if disabling the gps and location stops google and its apps from having access to your location data.

I dont trust them to honour the pressing of a button to disable anything, when location and advertising is so important to them, and their other surveillance friends

There’s this one from a quick search on IzzyOnDroid.

Disclaimer: I haven’t tested it.