They will be scenes we recognize, but not specifically recreated scenes from houses.
Look at commercials and press photos for some insight.
By “fan service,” I mean a house that requires a deeper understanding if the event’s history rather than a fairly superficial remembrance of the obvious.
In 2010, Hallow’d Past was the primary anniversary house. It predominantly featured easily recognizable scenes and characters that the majority of returning guests would remember (Scary Tales, Body Collectors, Icons) and a couple of deeper but identifiable cuts (Frightanic, Treaks & Foons).
Orfanage was explicitly for the fans (look at the spelling) who knew about Cindy and her original story where she burned downthe family home herself and escaped, to be placed in an orphanage. The vast majority of people didn’t know that story. But hard-core fans did. Fan service. But, it wasn’t the focus. That’s why they stuck it in Jaws queue (well and the fire).
This year, Icons is the easily accessible anniversary house. The icons are easily recognizable and their settings are, predominantly, tropes that even the most casual fan can look at and say “I get that reference.” There’s some more obscure references, but it’s predominantly a house for “everyone.”
SCary, similar to Orfanage, requires a much deeper knowledge of HHN history. It’s pulling much deeper cuts where canon is more important than popularity. To casual fans, it will likely feel like a completely original house with all new characters. People who have encyclopedic knowledge of the event, or who have been attending for 20 years, are going to have a far far deeper appreciation and understanding of what they’re seeing.