Good shift lenses for A7r?

[synn]

You cannot use the Speed Booster on the A7/A7r. It only works with the APSC e-mount cams.

[Christoph C. Feldhaim]

You cannot use the Speed Booster on the A7/A7r. It only works with the APSC e-mount cams.

LOL!
I totally forgot the A7R is FF ... funny fault ...

[qwz]

Nope.
You can use it.
On A7r you can choose - get extra stop and use 16mp or use 36mp but bigger DOF.

[Wolfman]

Will T/S lenses which fit on the A7R with a metabones speedbooster still be usable, so they'd keep their virtual focal length?
Or will the optical design of a speedbooster make them unusable?

You should use the non-speed booster metabones adapter for Canon to Sony FE….it has no optics to get in the way.