This worked for me, using MSBuild 2019 and setting the value below for command line arguments. This is in Jenkins 2.516.2 with all plugins up-to-date and MSBUILD plugin version 1.37.
/p:"ReferencePath=\"D:\data\jenkins\AdditionalAssemblies;D:\data\jenkins\AdditionalAssembliesVS2022\""
MSBuild requires quotes around the ReferencePath value if it contains a semicolon - otherwise, the bit behind the semicolon is treated as a separate parameter and MSBUILD reports an error like:
MSBUILD : error MSB1006: Property is not valid.
Switch: D:\data\jenkins\AdditionalAssembliesVS2022\
For some reason, Jenkins removes double as well as single quotes if they aren't escaped (and escaping them properly seems to be an adventure in itself). I'm not sure why or whether the ReferencePath parameter needs to be in quotes, after a lot of experimentation this is the first one that worked and I've already wasted too much time. What I don't understand is how there isn't proper documentation on how to do it, and it remained a mystery for decades (I, at least, wasn't able to find a solution).
For complete context, here's a screenshot of how I'm using it:
