This is DxOmarks conclusion:
The original Sony FE 70-200mm F2.8 GM OSS was already a very good performer, but it looks as if pressure from rivals (Canon’s RF 70-200mm F2.8 weighs just 1070 g) to lower the weight in this type has resulted in this newer GM2 version. Against its predecessor and the relatively new Nikon Nikkor Z 70-200mm F2.8 VR S (which at 1440 g is just 40 g less than the original Sony), the Sony FE 70-200mm F2.8 GM OSS II performs well and comes out in front, but it’s not by a large margin. While the weight advantage is nice to have the new model comes with quite a hefty price tag attached.
Sony 70-200mm GM II Lens at BHphoto, Amazon, Adorama. BuyDig. FocusCamera. FotoKoch DE, Calumet DE, WexUK, ParkUK.