[jwi]

I know nothing, what are some good sport climbing crags not that far from ... Tre Cime, say? I know of Arco of course, but it is also early August by the time I get there.

[Muenchener]

I once visited Cita dei Sassi on the Sellajoch in late October and determined that - under the thin layer of snow-covered verglas - it looked like it would be a good summer venue.

[Nibile]

Città dei Sassi is indeed brilliant, especially for bouldering.
There's sport up to (hard) 7c IIRC.
Otherwise Pian Schiavaneis, not pretty (chipped) but historical up to (hard) 8c.
Both quite close to Selva and Canazei.

[duncan]

The Citta dei Sassi is certainly superbly situated.

Also on the Sella Pass, Cogoi (Pian Schiavaneis) looks decent, has plenty to do in the 7s and up, and was fairly popular when I was last there. The pin in the UKC logbook seems to  be in the wrong place but it’s 15 mins. from the road and easy to find. 

Edit: I hadn’t seen Nibile’s post mentioning the chipping.

Lots of great multipitch sport of course...