It is kinda hard, also you would have to refeed in those 3 days after each fast, theoretically you would not have this much time to recover.
Also it is extremely mentally challenging and hardly sustainable with a normal life.
Just consider the re feeding part, so first day liquids, second starting with solids and third get also the big carbos. The fast again. This if you want t do it properly.
IMO it’s better a 10 day long fast than this. If you want to do it intermittent like you mentioned I would consider more the 1day option.