There are indeed a lot to list.
All of these are some examples of Symmetrical:
Since I have shown you all these, don't you think the answer to your question would be no? If you think it or not....the answer issss... NO.
Hope I was a help! ^_^
no for example kingler has a larger claw on one arm
No, because Rotom wash doesn't have a hose on both sides of it. (Thats just an example)
No if you just look at certain Pokemon you will notice. Kyurem is one and kingler spinda I don't think meloetta. There are a lot more but those were just the ones on the top of my head.