The only way to do so is to parse the trp files (they're actually XML files) which contain the project's model definitions, and look for the requiredPermission attribute of each element.
Use Miscellaneous/Parse XML to parse the files. Parsing is performed based on the data structure defined on its <Parsed Tree> exit.
To create the structure you can use the Import XML Data Structure by Example wizard (File > Import... > Tersus > Import XML Data Structure by Example) providing it with one of the trp files.
I recommend using as large a trp file as you find, as it will probably contain a larger proportion of the XML elements and attributes in use. However, the chance of a single trp covering all of the elements/attributes is slim to non-existant, so once you start parsing other files, you'll encounter exceptions, which you can resolve by manually adding the neccesary elements to the data structure created by the wizard.
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