Vector PM diagrams (top panels) and CMDs (bottom panels) to illustrate the selection process, taking the GC Minni 332 as an example. Left panels: original Gaia EDR3 diagrams containing all stars matched with near-IR VVVX photometry within a 1 degree field. Middle panels: subset of Sgr PM selected diagrams within a 1 degree field. Right panels: final PM selected GC diagrams within 3 arcmin from the center of Minni 332.