To give some life to this thread, I'll add to the current speculation with extra thoughts...
Halloween 3 (Waterworld) - enough said.
TCM (Mummy) - The new 2021 sequel movie (set 40 years later), will cancel out all sequels (including TCM 3D). It is a direct sequel to the 70s original, so it makes sense this maze would be similar to the one in 2012. I'm expecting recycled sets/props from 2016/2017.
TWD Attraction - while I do expect this venue to be used, I do NOT expect it to be TWD. The most obvious reason being that Universal would probably have to pay AMC since it isn't an IP they own. So I think we might see a retheme for HHN...
Parisian Courtyard - Could be an original, original based on a past SZ, or an IP. We've seen each type of maze here.. I could see Universal Monsters returning to this location.
Curious George - Yay new location! I'm guessing they might use the Studio Tour queue for this maze. It's the closest if you look at a satellite image.
BEETLEJUICE (SS29) - I'd be surprised if Hollywood didn't get this IP maze or this location. Maybe instead of plain black walls, Murdy will give us black/white striped walls instead!
I don't see Hill House happening obviously, but IF we did get another IP maze this year, I would say that "Creepshow 2.0" is very possible. If not, I speculate we'll see an original maze to help budget.
Something I haven't really seen mentioned is possible SZ themes & locations. Realistically speaking- Entrance, NY Facade, French St & Lower Lot. Looking at past events & the current year, here are TWO very possible IPs:
CHUCKY - This killer doll had a scarezone in 2013 to promote "Curse of Chucky". Terror Tram in 2017 for "Cult of Chucky". They own this franchise. AND there will be a NEW SyFy/USA series FALL 2021. It'd be an easy concept to revisit. Also they could throw Chucky back at the park entrance above guest relations like in 2019.
PURGE - Yea yea I can hear the groaning. BUT... this a Universal IP & a simple cheap high-energy SZ concept. Also, the final movie, "THE FOREVER PURGE" will be released July 2021.
French Street - I'd expect this to be the Parisian Courtyard maze finale like 2018/2019.
Entrance/NY FACADE - I'd expect an original themed SZ in these areas (or The Purge). But the only thing that NEEDS to happen is the return of the flame tower!
Lower Lot - Chainsaws 2.0.... unless that's too many chainsaws due to TCM being right there lol.. or just randomly have the SAW pigs due to SPIRAL.
I expect us to only get 6 mazes & 4 SZs, but as of right now, I'm not expecting any shows (outside of entrance Chucky) or Terror Tram (despite it being mentioned on the recent survey). IF we did get Terror Tram, they do have the area behind Bates to play with since Whoville is gone.