Where are the printer driver settings on Big Sur as on Win 10

You cannot depend on a printer vendor to create precisely the same print panel for the same device on two entirely different operating systems. The libraries and implementation tools for the vendor are different. By clicking the Show Details on that image you posted of the print panel, you will see more configuration options.

For the Expression XP760, Epson released a version 10.85 driver in early Nov 2020, which was still before Big Sur was released by Apple. They also released a version 5.8.9 Image Capture driver (ICA) in Jan 2021. These are the only two Epson drivers that would be compatible with Big Sur. No other Epson software was released recently enough (e.g. Scan 2, etc.).

The act of installing a driver does not automatically associate it with the Epson device. You need to visit System Preferences > Printers & Scanners panel, right-click on the XP760 entry, and choose Reset printing system… This will allow you to re-add the XP760 with the newly selected Epson drivers. Apple's Image Capture should detect the scanner on this device, if you installed the ICA driver (also on the linked driver page above).

If the Expression XP-760 is networked (wireless/wired), it is also supported by Apple's built-in AirPrint drivers which eliminate the need for any Epson drivers. During the Printer re-add process described above, you would choose AirPrint instead of the Epson XP-760 drivers.

Well, I have always ignored that dialog as I have just one device, but it does sound quite ominous in its wording, and possibly overstepping what it will actually do in practice. It should only apply to the selected device, despite what it says.

The link goes to the default Epson driver page for the XP-760, and you have to change the default operating system detection selector to Big Sur, and then the driver I referenced above will appear:

Depends on the printer driver, but usually those are in the Popup menu that normally shows the App name that you are printing from. Make sure you have clicked the "Show Details" button (if there is one).

It all depends on what Epson provides. If you are using the AirPrint driver (built-in), it is not particularly feature-rich.

If Epson provides a driver that has those features, you'd be able to select them from there.

When you select the XP-760 in the Printers list, only it is reset, not other devices. On the Printers & Scanners panel, select the XP-760, and a panel will appear with [Open Print Queue…] and [Options & Supplies…] buttons. If Epson provides these, click the latter and the driver version is shown on the resulting panel.

In the screen shot Bottom Left is Icon called Show Details - click it and see what is inside / presented.