If you go to the S&W website and browse Pistols using M&P Shield 2.0 for the Series and .45 Auto for the Caliber as the selection field choices, 10 Shield .45 models just came up for me.
Of those 10 model options, 9 of them had Shield 45 slides marked with the M2.0 designation (but all of them came up as M2.0 models).
Here's one of them:
M&P(R)45 SHIELD M2.0™ Tritium Night Sights No Thumb Safety | Smith & Wesson
The only one which doesn't have the M2.0 on the slide is this one, but the model description states it's a 2.0 Shield.
M&P(R)45 SHIELD M2.0™ Thumb Safety | Smith & Wesson
If you just select M&P Shield for the Series, and .45, a list of 12 of them comes up, and all but 2 of them contain the M2.0 description (2 are PC models and don't contain the M2.0 language in their designation).
If you find the SKU Number that interests you, you might call and confirm with the factory that it's a M2.0 model. Or look at the language description on the box label.
However, it kinda looks like the newer Shield 45's are coming with the M2.0 marking on the slide.