I did that, not just SRAM but also ROM, to fool a MC68EZ328 successfully. It works well. PIO + DMA does it well. Specifically i replaced rom & ram in an old Palm Pilot with an RP2040:

https://photos.app.goo.gl/KabVe5CrfckqnFEt7

https://photos.app.goo.gl/LGAkp6HoYAJc3Uft7

Edit: I did not yet update the rePalm article but much about that is in the Palm discord. https://discord.gg/qs8wQ4Bf

see #repalm-project channel