I think it will maybe help to taxonomize a bunch of different aesthetic views.
Aesthetic Non-Cognitivism - Non-cognitivists think aesthetic judgments like "Bwa mask dancing is energetic and powerful" and "This shade of green is vibrant and beautiful" do not express statements that can be true or false. You can be, for example, an expressivist or an emotivist, so you think aesthetic judgments are somehow expressions of feelings or other non-propositional representations.
Aesthetic Cognitivism - Not to be confused with a view about the relationship between art and knowledge that also gets labelled "aesthetic cognitivism," this is just the view that aesthetic evaluations like "Blok's verse is lyrical" or "These curtains are tacky" are truth-apt. They can be true or false. Typically it's thought that in order to be a realist or a relativist of either stripe you have to be a cognitivist. But there have been suggestions that you can be a realist without being a cognitivist in ethics, and I see no reason why we shouldn't think the same of the aesthetic domain.
Indexical Relativism - A view about the semantics of aesthetic evaluation. Aesthetic disagreement is sometimes merely apparent because the truth of the sentence "x is beautiful (graceful, elegant, sublime, tawdry, shabby, etc.)" actually means something different depending on who speaks it. "Shabby" means something different in Bohemian interior design than high modernist interior design or "graceful" means something different when I say it than when you say it. There is some sense in which disagreements don't share a topic or content. You can be an indexical relativist and an aesthetic realist.
Genuine Relativism - Also a view about the semantics of aesthetic evaluation. This is different from indexical relativism because it does suppose that there's topic agreement between speakers who are voicing aesthetic disagreement. But the truth conditions are relativized to the speaker. So when Marty and Sally disagree on some aesthetic matter, they are both taking about the same property when they say "X is beautiful" and "X is ~beautiful" and they are both right: "X is beautiful" is true for Marty and "X is ~beautiful" is true for Sally. This usually pairs with a response-dependence view and so is incompatible with realism.
Vulgar Relativism - As you can imagine this term is supposed to be a little derisive. But it should be clear that you can be a relativist without saying something silly. A vulgar relativist is someone who just doesn't see the point of aesthetic disputes because they don't see any capacity to switch over to another community or viewpoint. All disputes are notional rather than real.
Aesthetic Realism - The view that there are some mind- or subject-independent aesthetic value facts or that there is something the world is like aesthetically that is independent of our attitudes. Importantly these facts can be anchored in social practices and attitudes without being grounded in them.
Aesthetic Nihilism - Good news: aesthetic judgments are truth-apt. Bad news: all of them are false! (But good news again: no one has ever defended this view in print.)
Aesthetic Anti-Realism - Just a rejection of the above: aesthetic facts are grounded in our attitudes, dispositions, desires, reactions, etc.
Aesthetic Naturalism - The view that aesthetic value facts are natural facts. In other words, facts about aesthetic value are grounded in facts about the natural world. Two objects cannot be the same physically (biologically, chemically, institutionally) and differ aesthetically if you believe this.
Aesthetic Non-Naturalism - Again, just a rejection of the above. There are aesthetic facts over and above natural facts.
Frequently Asked Questions
Wait, so if I'm a realist then I think aesthetic value has nothing to do with pleasure?
Not quite. Take Auburn realism, a family of views being developed by the high powered aesthetics department at Auburn, for example. James Shelley has a view on which aesthetically valuable objects please because they're good; they're not good because they please. Keren Gorodeisky develops a neo-Kantian view in the Auburn realist vein that says aesthetic value merits pleasure but it isn't pleasure. Of course, you can think emotional, hedonic, etc. responses are only contingently related to aesthetic goodness. Nothing about aesthetic realism forces you to answer one way or another.
Do I have to think aesthetic realism is true in order to think that aesthetic value is normative?
Probably not! You could think that aesthetic norms are grounded in community expectations, rules, attitudes, etc. (so this is a stronger view than the network theory, which says they're anchored in community attitudes, etc.) and still think this makes room for aesthetic disputes that can be resolved by appeal to community norms. Similarly: it's not clear if Kant is an aesthetic realist. But he does think that aesthetic judgments command universal assent and they are in some sense procedurally objective.
Is there a route from normativity to realism?
Yes, it's probably going to be an inference to the best explanation. You just have to show how it makes sense of aesthetic experiences, the semantics of aesthetic judgments, and a whole bunch of other stuff better than the alternatives.