In project Panel, we should be able to replace a Composition everywhere it's used in all comp by another one.
For example : select a composition/ right clic it / replace everywhere with other composition/ in a pop up dialogue box, there would be 2 lists : 1- select the compo to replace with 2- in what (where ) compositions do you want to replace it, we can select the composition to swap with by checking in the box in a list.
David Simons (Adobe) commented
You can already do this, but it's quite hidden: select the new comp in the project panel and option-drag (or alt-drag on windows) that comp onto the comp-to-be-replaced's icon in the project panel.
If the Info panel is showing, it will say "Replace usage of <Comp1> with <Comp2>" to give a clue as to what will happen.
So this request could be considered "Make 'Replace Usage' easier to discover"