though there are lots of overlapping metro areas.

And some metro areas that will be non starters.

I suspect that there will only be 16 sites used (one for each group). Placement will largely correspond to metro areas.

1. New York (Metlife; grass could be paletized, 82,500)
2. LA (Rosebowl (92,542))
3. Chicago (Soldiers Field (61K)
4. DFW (Jerry's World 80,000; grass could be paletized)
5. Houston (NRG Stadium)
6. Baltimore/Washington (FedEx Field 82,000)
7. Philadelphia (Lincoln Financial 68,532)
8. Miami (Hard Rock 65,326)
9. Atlanta (Mercedes-Benz Stadium ?????, grass could be paletized)
10. Boston (Gillette 68,756)
11. SFO (Levi 68,500)
12. Phoenix (Sun Devil 73,378 or UoP 63,400)
13. Detroit (Ford Field 65,000 grass could be paletized, or Spartan Stadium 75K, or Michigan Stadium 108K, grass could be paletized)
14. Seattle (Husky Stadium 72,500, grass could be paletized or CenturyLink 67,000, grass could be paletized)
15. MSP (US Bank 66K, grass could be paletized)

-- Could see 4 NE cooridor sites reduced to 2 or 3.
16. San Diego (Qualcomm 71,294)
17. Tampa
18. Denver
19. Baltimore
20. Charlotte

Lots of options without having to go to far a field college stadia like Bever or Neyland).

Giants Stadium and Pontiac Stadium. They also used Orlando, which had grass then but FieldTurf now.

In Arizona, only U. of Phoenix Stadium is a realistic option. They're not going to play Cup games outdoors in 100+ temperatures, not even at night.

Baltimore's football stadium went back to grass this year, so it could host. The Redskins might have a new stadium in DC by 2026.

Cleveland didn't host in 1994, as the Mistake by the Lake was still in use. It could host in 2026. Pittsburgh is another possibility, as is Columbus (Ohio Stadium, which would need palletized grass).

When the Crew were playing there, they had the narrowest field in MLS.

But I would expect them to stick with large stadia in major metro areas and not venture into college stadiums.

I would expect no more than 16 sites, though LA could certainly host two pods. And Baltimore-Washington could also easily host two pods.

I'd be shocked to see Cleveland and Pittsburgh get games at the expense of other larger metro areas.

I think they would struggle to sell 108K tickets for two group round matches.

Ii'm sure there's enough CFB stadiums with grass in the south to get the job done.