I tried duplicating one side of my armature and mirroring it to the other side with Shift+D, S, X, -1. It works except that in pose mode, the arm and the leg are not symmetrical to the other side. Is there a way to fix it other than manually replacing them? I really want to keep it clean. The rest position is ok though.
I'm new to blender but I think you can remove on a object like one hand and the select the arm go to modifiers and add a new modifier called "Mirror"maybe it'll work for you. Through mirroring any change you can make in one hand is also applicable to second hand... Thank you!