I might be wrong but the biggest difference between Tweenmotin and Unreal studio I found is baking light.
Unreal studio can generate very high-quality GI and light effects with the baking light feature. Twinmotion seems to have just screenspace GI and Dynamic lighting which you don’t need to bake lights but it doesn’t have a good quality to it comparing to Unreal studio. However, Twinmotion still has OK and acceptable quality considering the learning curve.
Also, I’m not sure if Twinmotion supports Raytracing reflection which allows you to have a scientifically correct reflection. Sometimes, reflection prob(fack reflection) doesn’t really work with what you want to achieve.
Correct me if I’m wrong but Twinmotion doesn’t have a collision capability so it might not be possible to make first-person gaming like a walkthrough.