Scan to USB is a service within Workflow Scanning.
It should, if set up properly, automatically prompt you when you load a USB stick in the MFP.
Like this:
Pretty much all Xerox devices do the same thing, the same way and run the same app (Workflow Scanning)
The VersaLink family (Made by FujiXerox) has a USB option on the screen. Their (FujiXerox) older products tended to have a Store to USB feature.