To be fair, nearly every LCD TV I’ve worked with will happily display 60Hz… but also 50Hz, and frequently “59”, 30, 25, 24, and “23”. All that’s needed is for the video driver to expose these modes, but they often don’t by default. For example, I have to set a “custom resolution” in the Radeon settings panel to get 50Hz to show up. (Even then, it frequently disappears on driver updates.)
Once you’ve got that mode added for whatever display driver you’re working with, it’s just a matter of selecting that in RA’s video settings. I’d recommend putting PAL games in their own folder, then setting the 50Hz mode and saving it as a “content directory override”; that’s what I do. It took a few tries for me to get it to work, but as long as there’s a “video_refresh_rate” line in the config file, it does!
Side note: A VRR (FreeSync, G-Sync) monitor can make things easier for cores that will set region based on the ROM’s info. Turn on “sync to exact content framerate” and no more worries, so long as everything you do is within the monitor’s range. Sadly, my monitor’s range is only 40–60Hz, and that makes NES, SNES, and the like stutter like mad because they run slightly above 60 and there’s no way to set a cap in RA to throttle it to range, so I use the solution above.