In Bambu Studio you can easily add a filament change at a layer by right clicking on the layer number on the slicer preview page. You can also add a manual pause at a layer by right clicking on the layer number. What you cannot do (as far as I can tell) is both. If you make a filament change the only option is to change the color or delete the filament change. If you add a pause right-clicking only gives you the option to delete the pause.
I want this feature because I occasionally want to print items with 8 colors. Ideally I would then let it finish the layer that used the 4th color, pause the print immediately, manually change all 4 filaments and then continue printing. The best I can do now is to add a pause on the layer before the fifth color change, change 3 of the filaments, and then add another pause on the layer after the fifth color change, and change the final filament. This is a bunch of extra work and time that would go away if I could just simply put a pause and a filament change on the same layer.