This is an existing feature in diagrams.net
It’s also a feature in figma I believe. If nothing else there is such thing as text styles and color palettes that users can save and mass apply.
Basically the idea is that you can right click a layer, with it’s fill, stroke, shadow etc effects applied, and then copy paste that over to a new object.
Would be even better if you could then save that style as part of a palette in a design system library.
I can explain more if needed.
The explanation is clear enough. We already have a task defined that is just waiting to get into our priorities: Taiga. I’ve attached your request so we can get back to it once we start designing it and also to keep track of the interest from the community.
We also have a related idea, which is to have a new asset type at the libraries that allows to store more than one property in it. Sometimes you want a style with text and color properties and there should not be the need to apply them separatelly, right?