What other novel has the same format as Frankenstein?

Answer 1

it may be argued- and it was written much later than Frankie- that Pinocchio, which retains the artificial life motive, was sort of a juvenile take-off on Frankenstein. Pinocchio , which means Wooden Eye, was published in l887.

The format of Frankenstein is an epistolary novel this means it is written in the form of a correspondence of letters. This is actually one of the earliest formats of novels. Dracula was written in this form.

for a list of epistolary novels see link.