How edge is base on percentage of winning chance. If you select for 50 percent winning chance then house edge is 2%. If you change the percentage of winning chance then the edge of the house will be changed accordingly.
I am surprised to see you provide completely wrong information in this case since I felt that you were an experienced gambler.
As @Mahdirakib mentioned above, house edge doesn't change consistently, but is actually a constant number which varies depending on the game and the site rules. Lower edge implies that the gambler has higher chances of winning basically.