That Link's Awakening HD fan game lasted for, like, a week, and that was barely anything beyond a direct copy. Could be there's nothing for the lawyers to litigate, or it could be they're building a broader case based on a cohesive body of evidence.
All that to say, don't mistake inaction for inability to act.
That's not how it works. Copyright infringement requires the company to defend its copyright. Companies are not allowed to just leave it for a bit if they do that then it's interpreted as them having abandoned their copyright.
Anyway there's absolutely nothing actionable because you cannot copyright basic ideas. You cannot copyright the idea of made up animals that you do things with.
Not only that, but it is not like any of the Pokemon games. Some of the character models are certainly uncanny, and other than pal spheres instead of pokeballs, the two games aren't even similar.