Think this went a bit unnoticed in the community ports of the Sonic 1 2 And CD Decompilations For Wii U + Sonic 1 Forever And Sonic 2 Absolute Mods : r/WiiUHacks

Sonic 1, 2, and CD Remake Decompilation, Page 3

Release][N3DS] Sonic 1 & 2 (2013) Decompilation port

Sonic 1, 2, and CD Remake Decompilation, Page 9

Sonic 1, 2, and CD Remake Decompilation, Page 3

Sonic 1, Sonic 2, and Sonic CD Ports on Retro Handhelds – Retro Game Corps

Sonic the Hedgehog (lost build of cancelled Amiga port of Sega Genesis platformer; 1992) - The Lost Media Wiki

Sonic CD + 1 + 2 Decomps for Wii U - The Independent Video Game Community

The Android versions of Sonic 1 & 2 have been decompiled and can be played on PC, Page 4

How to port Sonic 1 and 2 mobile on PC the right way! - Decompilation

Sonic the Hedgehog (lost build of cancelled Amiga port of Sega Genesis platformer; 1992) - The Lost Media Wiki