So less like Pico-8 or TIC-80, and more like Quadplay?
https://github.com/morgan3d/quadplay
https://morgan3d.github.io/quadplay/console/quadplay.html?ID...
https://github.com/morgan3d/quadplay
https://morgan3d.github.io/quadplay/console/quadplay.html?ID...
https://github.com/nesbox/TIC-80/wiki#pro-version
Edit: actually, reading https://github.com/morgan3d/quadplay/blob/main/LICENSE.md it looks like it's only partially free (not unlike markdeep, another of the author's projects).