Nice normal map without beveled edges I've got mesh with lots of holes, concavities and convexities. The problem is that it has no beveled edges and whole mesh is badly triangulated. I only need to bake a good normal map, but adding bevels requires to totally remesh it which will take so much time :/ Is there any quicker way to do that? Maybe I can get around this somehow? Maybe there's another map I can bake and transform  to normals with some PS plugins? BTW I'm going to bake it with xNormal (I have never baked anything straight with blender).

Any help would be appreciated.
Selecting one side of your mesh



Use inset I to get a border of quads



Repeat for surrounding sides



Select the boundary of the side and add a bevel.



With the faces of one side selected you can use Select Boundary Loop (in the select menu) to get the outer edge loop to bevel.