An ethical epistemology is when we act on beliefs for ethical reasons. Our practical epistemology is about our beliefs as measured by actions, so an ethical epistemology is about our beliefs as measured by actions when those actions seek an ethical end. In a sense, "belief" just means "practical belief" (in many contexts it does). So we can believe things ethically, according to ethical commitments. If those ethical commitments change, we will believe differently. And, to an extent, the world will be different in our eyes.