Open the game's mod folder, create a folder with any name. I called it 60FPS. Inside that new folder, create another called exefs. Inside that, put the ips file inside.
You don't need to backup anything. The firmware won't touch anything. Just grab the latest firmware and install it as normal. If something goes wrong, (which it really shouldn't), then it's no big deal. Just try again or download from another place.
Ignore the rude people here. I had this problem too. Go to settings > Graphics > Extensions. On Vulkan Dynamic State, put Extend Dynamic State all the way to the left. Have fun with the game. :)
There are a lot of factors to consider. Fallout 3 has been out for 17 years. In that time, a lot has been figured out, so making mods for that game is easy. Xenoblade Chronicles X DE has just released. Yeah, there's going to be stuff to work out. So "2 hours work" is not going to happen. Try...
They're talking about making the exclusive online content accessible offline. And to answer the question, it might be. So far the game is looking identical to the Wii U version. Not going to say it's it's possible yet, but it's likely doable.