Weight copying on a per-vertex basis is usually only possible within the same object, but with this addon, you can copy weights across different objects. It is intended to be used alongside the standard weight panel, but it can also be used as a standalone panel with a minimal interface, including a standard normalization button.
Use it the same way as the standard weight copy feature. It copies the weight of the last selected vertex to other selected vertices.
View 3D > Sidebar > Item Tab > Mio3 Copy Weight
No changelog for this release.
This extension does not require special permissions.
I love it.