Can you sous vide from frozen?
Yep! You sure can.
Just make sure to add some additional time to your cook to allow the meat to thaw. @ge0rge
I do it all the time. It's a very handy thing. I always vacuum pack for the freezer in singles or pairs. Then the protein portion of dinner is as easy as opening the freezer door and seeing what jumps out.
Another sous vide site recommends adding 50% to the planned cooking time so a frozen steak would be 90 minutes instead of 60 for fresh. I have found this "rule of thumb" works very well and easy to remember.