If you want to stay on the legal route, what you can do is :
- Buy an Odroid or Raspberry
- Install Recalbox
- Legally buy roms (SEGA Genesis classic collection on Steam or NeoGeo Classics on Humble Bunble)
The SEGA classics have about 60 great Genesis games with clear roms that can be used in any emulator and the NeoGeo have also the roms in clear with the BIOS that can also be played in an emulator.
If you have PS1 discs, you can easily dump them (using ImgBurn for instance) yourself and now, there is a method to extract the PS1 bios from the PS3 bios publicly available from Sony's website.
Lots of possibilities even if you want to stay in the legal zone.
As Myself I wanted to also cover PS2, I decided to go with an ASRock DeskMini with a Ryzen 5 5600G. It's much more expensive though.