MET Law HUF, all easily self studied using John advice above. Systems, mixed bag a little but most would be capable of self studying, same with performance some struggle but most would be ok. Nav, probably 50/50 in my experience, I self studied but I wouldn’t recommend it, a good corse would have saved a lot of headache.
Flight planning, I won’t comment what I think your chances of that are but I’ll buy you a carton of your favourite if you manage it!
I’ve found that most will have a subject that they struggle with in the first 6, it’s just different for each person, all will struggle with Flight planning even if they do manage to pass.
If self studying my advice, use Avery for the study material and methods, and if you can get a hold of the AFT questions were good further practice.