Hiya. Thanks for checking my project.
You are right, although the code is made for some other YM variants, but this one is heavily optimized for YM2151, may have some problems with YM3812.

I'm working on the YM3812 version of the project like this https://twitter.com/fujix/status/1300049809353523202
It's working pretty good and I uploaded the source code at
https://github.com/Fujix1/NanoDrive_YM3812

Thanks! I will try that later

Whoa! It's actually working! You're such a good programmer! But You know what's better? Making it double! No FM chips even with 4 operators can compare with 2 operator 18 voices! There a lot of to do with it. Many DOS games support Sound Blaster Pro 1 in dual ym3812 mode. Also Furnace Tracker now available with ym3812 support. So now it's easy to make music for multiple amount of FM chips at the same time in one track. It would be awesome!

Can you please make dual version?

Acutally it is not very difficult,
I have done that with YM2203 already, you can make it by replacing the FM chips with YM3812.
btw where can I get vgm files using YM3812s ?

Here. I found track on VGMRips that uses dual YM3812 https://vgmrips.net/packs/pack/battlantis-arcade

It's actually pretty hard to find vgms for dual yms. But easy to rip from DOSBOX or compose in Furnace Tracker.

OK, thank you for finding out files.
btw, now I'm working on a PCB for this system, almost.