This takes me back; when I was young—probably around 12 or so—I used to create paper Transformers pretty much like these, though not nearly as elaborate. All I used was white paper, masking tape and small modelling sticks. Basically, I’d draw the design I’d want on the paper, usually in several pieces. Sometimes I’d color them. They were drawn to be foldable, with overlapping tabs for the tape and/or sticks to attach to. And they transformed, which of course was essential.
None survived to this day, of course. But they’re fun to do; maybe I’ll make some for the kids.