Personally I think your best bet would be to use a bluetooth mouse with your iPad, which will give you a cursor on the screen, a small circle, which you can edit using the Accessibility menu pointer settings, and it will be recorded on your screen recordings as well.
You say you don’t use a mouse, however I think this is going to be the best way.
Doing it this way will eliminate any need for the use of other apps, and a bluetooth mouse can be had quite cheaply on Amazon.
Of course it can also be done very easily using a separate keyboard, but that will incur a far greater expense.