Agree.
Strange Supreme was a legitimate match for Infinity Ultron, who used the IG to a FAR greater capacity than Thanos ever displayed(he casually negated and then "ate" one of Ultron's galaxy-busters, ffs.) He'd beat Thanos with low/mid-diff, imo.
As for Strange Supreme vs MoM Wanda: well aside from the fact that Strange just seems to be overall more powerful, he also has the time stone at his disposal, which I don't believe Wanda has any real counter for. So she probably goes down with low/mid-diff as well.
...Or Strange just waits for Wanda and Thanos to directly clash(which would be in-line with their history), and traps them both in a pocket reality ftw.
This just seems like Strange's fight to lose.