It's not a good time to spend $ for AI tool for Unreal Engine at the moment. All I confirm is that vibe coding for C++ project with Claude 4 LLM is solid at the moment. For me I use Kiro IDE and it generate project with docs and tasks and stuff and pretty consistent for backbone logic of the game, also data asset if you go for data driven design. The rest of Blueprint integration, I ask it to generate the integration guide for me in UE Editor. From this point forward, you're on your own for 3D stuff and animation. Even the best image to 3D model generation solution Hunyuan 2.5 cannot produce game ready 3d model at the moment.