welcome to the community. Developing such a functionality is possible of course. However I think this is not really extendable via plugins if I remember right. So I see just two ways here:
a) develop it into the core of the metadata editor as one additional authority source beside, dante, viaf, geonames, easydb and GND.
b) develop this functinality as a separate step plugin that brings its own user interface, shows maybe some of the metadata fields and allows to request your authority from there.
I guess a) is a bit complex as the metadata editor is one of the most complex (aka dirty) parts of Goobi workflow. This might be a bit to difficult for a first development on Goobi at all. So I would go for b) if I were you. A good starting point for such a plugin could be this one here as reference:
It does show metadata from the METS file and allows to update information there as well. This could be handy to look how typical things are done.
Another good sample which is a lot easier would be this one:
Let me know if this helps you, ok?
All the best,