If you can provide more context on where you heard the term "emuosv10" (e.g., was it for a specific handheld device, a PC, or a phone?), I can give you a more specific answer.
Pressing (default: Select + Start on Xbox pad) brings up the RGUI (RetroArch’s menu) with options:
While EMUOS V10 Free is designed to "just work," advanced users can tweak:
: Everything runs in the browser via JavaScript and emulators. Cross-Platform