Drag and Drop Nodes to Different Vendors

I can appreciate your desire to keep things tidy and organized and intuitive.  I've had similar issues where equipment I believe should be discovered & listed as built by Vendor A is shown in Orion to be from Vendor B.

I suspect this is due in part to the MIBs and OIDs and company history of a given business.  For example, when I first started working with Nortel branded equipment, it was showing up in several groups--most notably in RapidCity gear.  A little digging showed the OID's were registered to RapidCity instead of Nortel, due to RapidCity being the one-hundred-year-plus-old original vendor for the telegraph equipment, even as Bell Canada was nearly as old, and the early telephony vendor.  As vendors were gobbled up, I'd see Wellfleet, SynOptics, Bay, New Oak, and others showing up either in RapidCity's vendor group in NPM, or in their own non-Nortel groups.  Timeline of Nortel - Wikipedia  and Bay Networks - Wikipedia

Worse, Cisco modules within HP SAN hardware would have the full Cisco interface & IOS CLI syntax, but showed up as HP devices instead of Cisco.  Very confusing.

I suspect there may not be a good / intuitive / Orion-platform-friendly way to do what you ask, since Orion categorizes by OID and Vendor MIB, not by something that can be changed by us.  But I wish you good luck!