add color from libraries to swatches
Trying to add colors from the Libraries panel to the Swatches panel.
No logical button or menu item in Swatches panel nor Libraries panel to accomplish this task. Nor does dragging and dropping from Libraries to Swatches work.
I should say, no "easy" way to do this other than selecting an object, selecting the color in the Libraries panel, then adding to swatches.

-
Hari Vallabha commented
Hi,
On the latest photoshop, clicking colours or colour themes in the libraries panel populates the selected colour in swatches too. Please find the attached video for reference.
And please let us know if we can answer any other questions.
Thank you,
Hari Vallabha
CCLibraries