I’ve got the same problem with the ET-3750.
No solution found, but as workaround I set up the Cloud print and scan function via Epson Connect Services. This sends me scans via email.
The best solution I have found is to install the software “VueScan” on flathub for non-cloud scanning. I turned off the VPN I was using and VueScan discovered my EPSON ET-3850 scanner instantly.
I did pay for the full license for Vue Scan in this instance because of the build quality of the software when testing it for free, with VPN off, to see if it could detect my scanner and it did.