The group I’ve been doing training with requires a 2.5 lb or larger ABC rated extinguisher. That being said, nothing says I couldn’t also have one (or more) of these Element extinguishers in addition to the traditional type.
I looked at these and their competitors, I found most of them have no ratings at all as far as ABC either. From what I read elsewhere nobody has tested them to anything close to UL standards. Having an extra fire extinguisher is always good. They are a bit of a mystery as to what they will actually put out.