These are ones I’ve been able to discern through either the knowledge base documentation, experimentation, forum posts or users mentioning (list doesn’t include anything specific to ID3 tags (of which I’ve no knowledge nor desire to acquire any):
ALBUM
ALBUMARTIST
ARRANGER
ARTIST
BARCODE
CATALOG
CATALOGNUMBER
COMPOSER
CONDUCTOR
COUNTRY
DATE
DISCNUMBER
ENGINEER
ENSEMBLE
GENRE
IMPORTDATE
INVOLVEDPEOPLE^
LABEL
LIVE
LYRICIST
LYRICS
MIXER
ORIGINALDATE
ORIGINALRELEASEDATE
PART
PERFORMANCEDATE
PERFORMER
PERSONNEL^
PRODUCER
RECORDINGENDDATE
RECORDINGLOCATION
RECORDINGSTARTDATE
RELEASECOUNTRY
REMIXER
ROONALBUMTAG
ROONRADIOBAN
ROONTRACKTAG
SECTION
SOLOIST
STYLE
TITLE
TRACK
UPC
VERSION
WORK
WORKID
WRITER
^ = resolves to same Roon data points. Form = INVOLVEDPEOPLE=name - credit_role OR PERSONNEL=name - credit_role where credit role is defined here: