How to mark sharp by angle? I try to mark sharp, but I found the only way is to select it one by one and mark in edge menu, is there a way to do it by angle just like auto smooth or edge split?
and then I want to turn sharp into seam , how to do it??
You can do this easily using the Select Sharp Edges function.

Use Select &gt; Select Sharp Edges and adjust the angle.
Now you can mark all selected edges as sharp

To turn all sharp eges into UV seams.

Select one sharp edge
Use Select &gt; Similar &gt; Sharpness and mark the edges as seams