OK so what you have here does fit the GBZ style -- somewhat -- and your style is rather consistent in some aspects, so good job on that. My only advice is you keep it up, practice and practice. It may take a while but even an amateur like myself can eventually master the GBZ style to a T. There is a lack of shading in your sprites besides the Wizzrobes which have too much shading in my opinion. You need to strike that perfect balance; try looking up some of the official sprites and see how they're designed. You'll notice they generally have minimal colours but still enough shading to have depth to them, a simplistic but pleasing charm. You're definitely are at a good start though.

As for you boss health meter, I'd say it fits classic more due to the lack of outlines. I'd say each "bar" of health needs to be at least 8x8, I think. Otherwise, it's a nice start and overall your sprites look fairly competent.