I've never done it, and I don't know such software, but it shouldn't be too difficult to write something (a program, VB-script or Powershell-script, or a combination of those) that reads through all those images and maintains a database with all tags and the pictures that contain them. Once you have that, you need a program that searches in that database (takes a second at most) and shows all pics that you searched for,
Let your manager make a change request (or whatever the procedures at your company are) for the IT-department. When they have an estimate of the costs, make a business case, get the necessary permission and money and go for it.
I work with a company that has thousands of images in different network folders. We want to find a way to easily search for images using tags, but in a way that searches in all drives at once and without taking forever. I've tried using the folder's tag system but it takes about 10 minutes to search in one drive, to search in all of them at the same time seems like would take over 30 minutes.
We use Lightroom for photo editing and exporting for web, etc. But we cannot have someone in a different computer search the catalog through the network.
Is there some any software/plug-in that would search for tags without having to import the files into it and/or disrupting the network folders that are already set up?

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