In my project I am using a CM2009 IC between precise VGA controller and VGA output connector. It is really pointed out in the datasheet for this IC which i can use EMI filters on HSYNC, VSYNC and DDC channels proper right after IC and prior to VGA connector. While https://garrettdhrst.blogoxo.com/31353144/the-fact-about-emi-filter-vs-emc-filter-that-no-one-is-suggesting