Mannequin pose modification

Hello I’m quiet new to Unreal Engine and currently learning how to pose a Character in Unreal. I’m currently working on 2D cinematic project incorporating steelshots of 3D character model.
I recently learned how to use Animation Retargeting to transfer poses from Mannequin to my character and I found it very useful and efficient. Downside is I don’t know how to pose a Mannequin in unreal, aside from bring it to Maya, pose it, and bring it back to Unreal for retargeting process. The process takes too much time for project I’m working on, so can anyone tell me how to pose Mannequin in Unreal without going back and forth with other tools (or is there a way to do so in unreal)?