Sobate only IF you are going to backsweeten and then a few days to a week before you backsweeten.
Clarifing agents... The sooner you use them the sooner you know that your wine is clear BUT time is also a great clarifier. Some Fruit wines even defy the clock and can hold a haze longer than most of us can wait so for some fruit wines you hit it with everything.
That said if it starts to clear on its own soon (week or two) after your first post fermentation racking - wait it out.
I'd always rather add as few chemicals and take as few actions as possible. Everything you add and every time you handle it is just another opportunity for a bacteria or contamination to happen. So sit back and wait or go start another hobby while you wait.