Hi!
Yes, remote debugging should still work fine 
If you are trying to debug Firefox for Android on your emulator, be aware that it is based on Firefox ESR (v68), so you need to connect to it from Firefox Desktop ESR68.
You can download Firefox ESR at Download Firefox in English (US) and more than 90 other languages
Our backward compatibility policy only supports a gap of 2 versions. This means that Firefox for Android (aka Fennec) can only be debugged from: Firefox 68, Firefox 69 and Firefox 70. Since Firefox release channel is now Firefox 72, the only compatible release officially available is ESR68.