If emulating on a PC, I still recommend Magic Engine. It is French, a bit old and requires a key, but I have shared that key with you.

I’m a bit spoiled with a real NEC TurboDuo that has been recapped, an Everdrive card, and a decent collection of TG-16 CD / PC-Engine Super CD-ROM2 original disks.

[img]https://i.postimg.cc/FskG1wr1/F78-E3-BE0-4884-4-D09-9-D01-7714511-B5142.jpg[/img]

Not too much. I only played Beyond Shadowgate in RetroArch for a bit (there's two PC-Engine cores, based on Mednafen.) Seems to work fine:

[url=https://i.imgur.com/B8mYqGP.png][img]https://i.imgur.com/B8mYqGPl.png[/img][/url]

As always with these things, you need to get the PC-Engine BIOS ROMs. There's a BIOS collection for several emulated systems here:

https://archive.org/details/2019_07_21_RetroArch_Libretro_BIOS

Have any of you guys ever messed around with Turbo-Duo (PC-Engine) emulation?