The new update firmware for the Canon EOS R5 and Canon EOS C70 is based on user feedback however, this will improved workflow, and enhance lens compatibility and functionality for other canon products.
Once Canon EOS R5 is updated this will make it fully compatible using an EOS R adapter with two EF-mount cine zoom lenses, the Canon CN-E18-80mm T4.4 L IS KAS S, and the Canon CN-E70-200mm T4.4 L IS. While the Canon EOS C70 will be more comprehensive, simple and will include an HDMI View Assist feature, which allows for a Wide DR/BT.709 LUT to be displayed over HDMI when shooting in a Canon Log gamma.