EOS R makes the most sense to me.
The crop in 4K actually works in your favor because the majority of your lenses are EF-S lenses anyways, which are APSC and not full frame. It is much easier to adapter vintage lenses with the RF mount too. So the EOS R is more future proof.
Or you can try out other brands as suggested by other posts. Panasonic and Sony are both great camera brands for videography, for example.