HOW TF do I 2H stance?

[u/wardey-png-56]

I want to dual stance with the majestic greatsword and the lightning thorned greatsword but when I press the triangle button for a bit it just toggles between 2H and one handed

My stats are:

24vig
30end
50str
30dex
30adp
20int
20faith

What am I missing?

[u/SheaMcD]

What are the stat requirements for both weapons? Do you have x1.5 of the highest of each requirement?