Therefore a looked first after the used plugin for viewing and playing and I saw that the 4K files from my Osmo DJI (AVC) and GoPro 7 HEVC (both 50p) and the FHD files of my smartphone used the SO4 compound plug and only FHD 50 p of my Panasonic (MTS files) use the compound plug.
Than I put of every file a small amount in a 4K project, 50p GoPro followed by DJI Osmo, Panasonic and smartphone, played and rendered to different UHD Magix templates (using QSV and/or NVENC) and also showed the different hardware uses on my toolbar.
I also show my default settings for Video and File I/O in this build.
Very pleased with the results !
Look the made video of the "Vegas Capture" of VPro 18 that was running together all on laptop from signature: