In theory, a 3D world with "standing" 2D sprites is not very hard to implement. Though the game in question has a lot more going on, which makes creating something like it quite a complex task.
Im gonna take a more "philosophical" route with this comment, because it is certainly possible to create something like this in Godot, however, its gonna take a lot of work, and also perhaps multiple people.
Godot makes it pretty easy to get into game development, even if you have no former experience in programming. The docs are sometimes a bit meh, but if you put the effort in you are gonna get there, also there is the community if you have a question.
There are many accounts of great games, developed by only one person. Some claim to not even have had any programming experience before, but they still did it.
The developer of "The first tree" gave a great talk about his experiences: https://www.youtube.com/watch?v=g5f7yixtQPc
Octopath traveller is, no doubts, a work of a big team, of a big company. But this doesnt mean that one person, or a small team, cannot achieve something similar. It may just be a matter of scope, if you are just starting out, it is most likely far too much and just too daunting of a project. But you could try to implement similar mechanics, or create small games that use some subset of those mechanics. By taking small steps, you gain the skillset necessary and, maybe more importantly, the know-how of how to pull off all these different mechanics.
Finally, it is most certainly possible in Godot. The difficulty, though, like for any big game, is way up there, probably far too high for a potato.
Game development needs a lot of dedication, its frustrating, but also very rewarding. If its already a long-term interest for you, you are gonna find a lot of enjoyment in it.
I'd say, just try. It's gonna need a lot of small steps, a looooooooot of tutorials, and you are gonna need a lot of patience. But in the end, you might just get somewhere with it.