F8 is easier to study, but harder to pass. F8 won’t require that much of accounting background. But on the other side , you are studying for acca, that means u should get into f7 ! that’s your base! ..the core!
F8 is theory, and many people can’t study theory 🙂 they even even hear this word. But subjects are EXTREMELY time pressured and both are quite hard comparing other disciplines. Try to take a look at their syllabus and past papers and think which one seems more manageable for you. but keep in mind that they both require lots of efforts and lots of practice. Quick study in 5 days before exam won’t work.