I just took a look at the site's Folder Continet map and there's very obvious places for the next wave: a factory complex for ME, the cloudy mountaintop for WG and the open fields (with a "mini stonehenge" in one of them) for Virus Busters. Sadly I don't see a way to fit the remaining Fields yet. I suppose JT could co-exist with NS, but there's not an obvious place for DR. DA would obviously not be in the same map, so...
Before someone says I'm ignoring Unknow, it doesn't lend itself to a biome and it's suposed to be the mutants and weird mons who don't fit in the other fields.
You're not really understanding what they're doing here. The Pendulum Z isn't referencing the Alpha Evolve fields - it's referencing where Alpha Evolve got them from.
The original Digimon Pendulum had six waves - Nature Spirits (for beast, insectoid and mineral Digimon), Deep Savers (for marine Digimon), Nightmare Soldiers (for monsters and demons), Wind Guardians (for bird and plant Digimon), Metal Empire (for machine and mutant Digimon), and Virus Busters (for holy and 'heroic' Digimon). These are the six names mentioned on the Pendulum Z site, and these are the six fields shown in the initial announcement. These were also the fields in the original Hyper Colosseum card game, with Dark Area and Unknown added as well.
If there
were to be an extra three, it stands to reason that they would be Dragon's Roar, Armageddon Army, and Animal Colosseum - the three waves of the Pendulum Progress.
Alpha Evolve then categorized Digimon differently, adopting the name Dragon's Roar from the Pendulum Progress for dramon and dinosaur Digimon, and keeping Virus Busters, Deep Savers, and Metal Empire intact. Nightmare Soldiers absorbed Dark Area, and Unknown was dropped altogether, iirc. Wind Guardians became just birds and the plants were combined with the insects (similarly split out of Nature Spirits) to become Jungle Troopers (a name he made up wholesale). This made eight fields that were used from the start of Alpha Evolve, up until Digimon Story: Lost Evolution, which divided insects and plants to make nine fields (probably to correspond to the nine worlds held up by Yggdrasil in Norse myth), however it didn't give them names.
However, with insects featured in Nature Spirits Z, and the fact that literally everything is referencing the original Pendulums, it's safe to assume that Wind Guardians, Metal Empire and Virus Busters are the only others we can expect...maybe Dragon's Roar, Armageddon Army and Animal Colosseum at a stretch, but certainly not Jungle Troopers.