Bugfender can work with any engine supporting the use of external libraries.

We've got little experience with Unreal Engine ourselves but their website offers information on how to use a static library on iOS:
​https://wiki.unrealengine.com/Linking_Static_Libraries_Using_The_Build_System

On Android it seems a bit more involved: https://answers.unrealengine.com/questions/822567/ue420-aar-imports.html?sort=oldest
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