@bur There's no reason this shouldn't be possible - I saw Drastic DS emulator on Android has dual screen support - so at least on Android it's possible with Raspberry Pi. I'm waiting on a HDMI 3.5 inch screen so I can test it with my 5inch Waveshare screen, and I'll report back if I have any success.
As for doing it in Raspbian, I sure hope that would work but no idea at this point.

@mitu Worked!

Lots of the emulators don't have "versions" also. The libretro cores are constantly updated etc - there is no such thing as a "version" for many of them.

@antnned read up on the docs on this site. You can use the menu to exit emlationststion to the command line. I believe F4 on the keyboard also works.

I prefer to us Ssh. I use putty. For editing Es_systems.cfg I typically is an ftp client like WinSCP.