sharing styles between users

A designer makes designs with styles.
I have edit rights at the file.
I copy an element with (text) styles within.
But I do not get the styles.
I would like to get the whole design including the styles.
Is the solution that my designer has the professional version.
Or do I need to have the professional version as well?

After the design is finished, is it possible and easy to return to the free version?
For both of us, it is not our job, so we do not need the paid version for more projects.