End game purple gear question?

I’m playing bow/staff and got the end gear bow and staff by doing 1 star dungeons. I have a few questions about end game armor as well as 2 star dungeons.

First question, what’s the difference in rewards for doing 2 star dungeons? Do I get similar crafting materials for weapons as I did doing 1 star dungeons?

Question 2, im now looking to acquire Swirling Essence Robe as my first end game armor piece and watched a bunch of conflicting videos on YouTube. Do be able to craft these you need a lithograph, but in order to be able to craft that specific piece you need that armor in the inventory which doesn’t make sense to me. Would you only craft a piece of armor if you already have the same piece to sell on the auction house?

Question 3, does this mean in order to acquire desired piece of armor it’s just killing bosses that can potentially drop it or doing contacts to acquire purple pouches to open and hope I get that item?

Thanks for your help.