I have a question regarding PCIe to PCI bridges you can find on ebay, like this one

PCI-E Express X1 to Dual PCI Riser
https://www.ebay.com.au/itm/PCI-E-Express-X1- … m4383.l4275.c10

it uses the PI7C9X111SL and there is a datasheet for it on the pericom website (now diodes.com) along with a tool, PCIedit

https://www.diodes.com/assets/Datasheets/PI7C9X111SL.pdf
https://www.diodes.com/assets/Uploads/Registe … ng-PCIEdit2.zip

my question is
would it be possible to change PCI registers to maybe make it possible for a retro PCI sound card like a yamaha ymf744 to work on newer systems lacking native PCI?