The Plasma assistant detected the printer, but could not find any drivers. So, I first tried what has been working before: using a local package called epson-inkjet-printer-201204w-1.0.0-1lsb3.2.x86_64.rpm (which I downloaded and keep around) using either Discover or dnfdragora. Discover told me that the installation was successful, but the Plasma assistant still refused to see the driver.
When I used dnfdragora, it would not start and issue an error message about insufficient permissions. I made my user a sudoer, but it did not help.
Little did I know that the solution was a lot simpler that I expected.
All I had to do was to start dnfdragora and search "epson." This gave me a package with a newer version of the drivers, which I installed and, after that, I simply configured the printer with the plasma assistant, where the drivers could be selected this time.
For the scanner, I used megatotoro's procedure here again.
Now everything is good!