Super good question! It's difficult to answer for sure but the answer is basically "yeah probably".
I don't know much. There's a really good chance when you're reading this that I haven't even published any mods. I'm not into model or texture swapping and I don't know how to touch sound assets or hack any of the code. To be totally honest, I don't even know how much is possible and impossible.
I think you're in the wrong place if you're not looking for information about modding DRAGON QUEST XI S: Echoes of an Elusive Age, Definitive Edition. But maybe some stuff here is interesting to general Dragon Quest fans and maybe some of it is helpful for people modding Unreal Engine 4 games in general. Read and find out?
Right now I'm making a mod which has a lot to do with swapping the number-y "details" of items and monsters and shops and other data. Not so much Erdrea itself as the stuff in that world. That means I have to do a lot of poking around great big CSV files praying that whatever changes I try don't screw up my save or the world or any systems in this game.
Along the way, I'm running into problems and figuring out solutions. I mostly just want to document what I find. If the index is doing its job right then you should be able to find every subject I cover over there, and maybe narrow down on whatever's useful to you. Good luck!