Supplementary Material for "Identifying compact symmetric objects with high-precision VLBI and Gaia astrometry"

This Supplementary Material provides the extended data tables, figures, and methodological details supporting the analysis presented in the main paper ("Identifying  compact symmetric objects with high-precision VLBI and Gaia astrometry") which is accepted by Astronomy and Astrophysics (A&A). It includes the complete CSO candidate sample, parameter lists and additional diagnostic plots.