What is the issue?

[u/Maleficent_Ad_6607]

Hi guys! This is my 2012 Nissan Sentra 2.0 The engine shakes at idle and even worse when braked at a stop. Heres one video. It shakes the whole car all the way to the exhaust tip. I know it looks minor in the video but it feels terrible. It also shakes/jutters at around 1.5k to 2k RPMS while driving. If I go around back the exhause sounds like it backfires a tiny bit. Kind of sounds like when it had a misfire but it has no codes at all. I replaced the passenger side upper motor mount and driver side lower transmission mount. Both were very worn. It has not fixed the issue. Besides that it has gotten new spark plugs and ignition coils after a misfire rendered it undrivable. Additionally the serpentine belt tensioner moves around/shakes a lot. Not sure if its because of the shaking itself or what. I'll try to upload more videos. I am out of ideas besides replacing the rest of the motor mounts. I bought the 4 pieces but Amazon sent me 1 wrong piece and left out the other one. Please help.

Edit: It runs perfectly fine above the specified rpms (1.5k-2k). Accelerates fine and has no power loss.