We have been focused on the soundtracks, but what about soundfonts and other similar parts?
It seems that the NEC series are gaining the most attention, especially for perhaps Touhou games.
There is a PC-98 soundfont as well as a plug-in for BASSMIDI, but for Sharp X1 and X68000 style sound, there is VOPMex, but it's quite unuser-friendly. There hasn't been a YM2151 soundfont nor even with its related attachments such as OKI M6295.
FM TOWNS sadly doesn't have Alltynex nor other soundfonts that use its internal sound chip.
Here is a demonstration of the PC-98 soundfont playing Sonic Wings Assault - Tokyo:
https://clyp.it/qh2osovm