Doesn't that kind of defeat the point? If you have to make it thinner to bend it then the corner is only as strong as the thin section so you may as well be using thinner material anyway, and if you stick a weld on the inside you end up ruining its properties. I'm not saying don't do it, but there may be/probably are better alternatives.

A company I used to work for invested in a whole new breakpress specifically for hardox and domex as it was worth the initial out lay in comparison to all the work they had to do in mild steel.