Using default character rig animation in another characters

I want to buy an animation set from the marketplace but it use the default ue4 character so is there an easy way to adjust the animation set or make right for another character or I have to design my new character to have the same rig as the default unreal character
( Third person character)

It’s called “Animation Retargeting” in UE4. You can read more about it here: Animation Retargeting in Unreal Engine | Unreal Engine 5.3 Documentation

Quote from the official documentation:

Animation Retargeting is the process of repurposing existing animations for use between multiple characters, eliminating the need to create entirely new animations as you can instead share your animation assets between characters.

Basically it’s possible (most of the time). There are plenty of examples in the documentation and on YouTube. One of the steps in the process is rig setup where you assign bones from your skeleton to the rig nodes which will “transfer” animation from one skeletal mesh to the other one. It already sounds harder than it really is so I will stop here to not confuse you anymore.

Follow one of the examples to decide on your own if it’s easy or not. Good luck!