For the record, the functionality is way different between B&W Effects 2 and the B&W filter in Studio 2.
In Studio 2 the B&W filter is basic (Not saying you can’t produce similar end results using it in combination with other filters) but BWE2 has a range of canned effects and Presets, Adaptive Exposure, Dodge brushes, curves to name just a few.
B&W Effects 2 is just a plugin though that does require a host editor. It still works on Windows 10 as a plugin from Affinity Photo, and also from the original Studio (Classic, or Studio 1 or whatever that is now officially referred to), but it can’t be used from Studio 2.
It also needs to be registered, and that raises the question “Can you actually now get a registration key for it”.
I purchased and registered the original B&W Effects in 2013, then updated to B&W Effects2 when it was released, and I still use it occasionally. I certainly would not pay USD$ 55.99 for a plug-in that is no longer supported, even if it can still be registered, but equally in my view there are other products that offer as much and arguably more than Studio 2 for its USD$99.99 (AUD$134.61) price, particularly given the lack of development of that product over the last year.