A few days ago I wrote about the Cambo Actus Mini View Camera.
Novoflex also has a bellows system which can take Canon or Nikon or mirrorless cameras. A key distinction is that bellows systems have traditionally been ONLY for close-up and macro work with DSLRs, because the interposition of the bellows hardware does not allow infinity focus (when using a DSLR with a DSLR lens).
Novoflex has tilt/shift bellows for Canon/Nikon/Leica/Sony also (see Novoflex bellows at B&H). Rollei also has a bellows system. Some of these are relatively light and portable, and some are not. Also, movements of tilt/swing/rise/fall/shift capabilities vary. Although I recently ordered a used Nikon PB-4 bellows, the PB-4 cannot be used with mirrorless and cannot focus to infinity so it is for close range and macro work only.
The Novoflex web site is at best confusing, for example, not saying for whether or not infinity focus is possible with a Nikon or Canon lens when used with Sony mirrorless (the Cambo Actus Mini View Camera reaches infinity focus). All the right parts seem to be offered (e.g. a Sony mirrorless camera adapter), but the company does a poor job of explaining what works in terms of focus, and what does not. For example, the following omits what kind of camera is being referred to (presumably a DSLR):
For purposes were focusing to infinity (35mm and APS-C size sensor cameras) is required NOVOFLEX offers a special lens head by SCHNEIDER KREUZNACH (Apo DIGITAR 4,5/90mm), which is optimized for digital cameras. The focusing ranges from infinity to 1.2x magnification with 35mm cameras and up to 1.8x magnification with APS-C cameras. The lens head comes preassembled on the necessary adapter to start taking pictures immediately.
As yet I do not understand if a Nikon F-mount lens used with a Sony A7R II can reach infinity focus with the Novoflex system. Nor is it clear if Canon EF lenses can be electrically controlled when using a Sony mirrorless camera (it seems not).