First off, The Pocket and BMCC Speed Boosters came out aftermthr Cameras were released, so they had the camera. Next the IR Filtermis not the total sensor/cover glass stack, which is set for thr MFT FFD standard to allow MFT lenses to focus correctly. A Speed Booster needs to be set for this thickness.
Since the existing MFT Ultra and XL are working with the prototype csmeras, it might be safe,to,assume, thr new Pocket 4K complies to the existing standard used in the GH5S.
Anything else about this is pure speculation, and we need to wait until the camera has been released into the “wild”.
Cheers