Shared library for declarative stages?

I started researching shared libraries and whenever I tried searching for a way to re-use stages, the answer was to create a groovy script in a shared library and call that.

But what if my original stage works quite nicely within a declarative pipeline and the only thing I need is to store it for re-use so that I do not have to copy paste the whole stage (with post actions) to every single repository after the stage needs to be updated?

I would like to avoid the complexity of using scripts if possible, but have not found a way yet to do that.

Thank you in advance for any pointers or suggestions. Jenkins is a very interesting tool, just need to learn how to more efficiently use it.