SmartR90 - addon for Blender 2.8x
This Blender addon Allows to orient all selected UV islands vertically or horizontally (the greatest size is determined by bounding box)
Or another words - addon use "smart" method for rotation "wrong" rotated UV islands.
We will hope that we created small, but very helpful addon for your work.
Others helpful addons from our team.
Uv-Outfit – Merge - This Blender addon allows to merge multiple UV layers into a single one
Wlock Pro - An Addon Which Allows To Lock 3d View Rotation.
B-rename - An addon, which will help you to speed up the renaming of the objects for baking.
Emg (Edit Mode Guard) - Will show you a warning window if you accidentally press the TAB button to enter in edit mod, during work to very poligonal model (for example - 1 000 000 vertices)