The cant isn't adjustable. You order the amount (degree) of cant you want. I find that the 15 degree cant is a good angle for ease of draw and re-holstering from the hip (rear pocket) position. Unfortunately, I don't think the High Slide would work at all for cross draw, as it rides up so high, you'd never be able to bend at the waist. It's a real stiff holster and is made to fit over the rear pocket, and when used as such, it's very comfortable. Side Guard does make an appendix carry holster that might be better suited for cross draw. Check out the other holsters on the website. It's a small company run by a guy named Erik. He has a day job and this is just something he does because he loves doing it and he's good at it. Email him to see if he can do a cross draw for you. He has been known to do custom work in the past.
Joe
Thanks, Joe. Good info.