When you have a key frame set for A and one for B place another key frame (let’s call it A1) in between the 2 main keys but set the object off to the side a bit and you will see the trail curve. So when you hit play your object will move from A to A1 then B. BUT if the trail does not curve (if it shows a sharp turn) when placing A1 you will need to place key frames between A&A1 and between A1&B to create the curve you want. Make sense? Hope I didn’t confuse you.