So it's the face off at the final battle. However, Wong or some sorcerer decides to sum more help. Oops, the Marvel folks disappear and other forces take their place (not at once, each is a separate show). The new folks understand the need to take down Thanos and crew. Who does, who doesn't?
1. The Green Lantern Corps - let's go with the original 3600. No Ion, no Parallax, no other colors, just the first pre-COIE corps.
2. The Soul Society - everybody from the top folks to the everyday Soul Reapers
3. The Naruto ninja armies at full strength for the 4th Shinobi war
4. The assorted Kaiju from Godzilla vs. Kong - all in sync with Big G in charge
5. I was tempted to throw in my favorite Lensmen Galactic Patrol but 1000000 battleships, Children of the Lens and Arisians is something of big old stomp.
No blinking them away with the gauntlet.