Blackmagic URSA 12K LF has a Canon EF lens mount and currently there are 257 native lenses available for this mount.
The latest released lenses that are compatible with the URSA Cine 12K LF are the Samyang MF 14mm F2.8 Mk2, the Samyang MF 85mm F1.4 Mk2 and the Irix 45mm F1.4.
Blackmagic URSA 12K LF doesn't have a sensor based image stabilization system but
78 of these lenses already comes with optical image stabilization.
Since Blackmagic URSA 12K LF has a Full frame sensor, it has a focal length multiplier of 1× so lenses will provide their original focal length on URSA Cine 12K LF.
You may also also be interested in these:
Blackmagic URSA 12K LF Lenses with Image Stabilization
Blackmagic URSA 12K LF Lenses with Weather Sealings