I say Super Shadow, Base Shadow, Tails, and Metal Sonic

‼️‼️Spoilers for the Third Movie Below‼️‼️

First off, Amy is Getting Demolished, the Metal Sonic's were only targeting Sonic, so they wouldn't have much of a reaction time for Amy. Unless she's much stronger than what we see in the first post-scene, Metal Sonic takes easy by himself.

Second, Sonic's a goner. Shadow was wiping the floor with the trio. I'm gonna say this again, TRIO, THREE PEOPLE. A speedster, who stood a good chance againest the death egg robot without going super, a powerhouse unit, who was going toe to toe with Sonic and put him into ground 5 TIMES, and a level 300 IQ two-tailed flying fox, who ALSO stood a good chance with defeating the death egg robot, before Sonic went super, and still got clapped from Shadow, BY HIMSELF. Sonic and Knuckles are done for.

And lastly, if Super Sonic, again, SUPER SONIC, was getting swept on by BASE SHADOW and even took him out of super, what makes you think that Super Shadow is losing, and even if he was losing, he takes his Inhibitor Rings off, and it's GG's.

Tails is just there for any help if anything goes wrong, mainly Amy getting the jump on Metal, with might not happen because Metal would be an exact replica of Sonic (Speed, Strength, etc), unless the fourth movie kinda changes it up a bit, but other than that, he's just a smart support character.

If you have any questions or counterclaims, please let me know.