So, Flash vs Strange?
One reason it won't work is because of this auto shields. They aren't SUPER tough, but they pretty much allow him to be hit by lightening and even tossed in Lava. I don't think his auto shields canlast more than a second against Fllash.
His normal shield could keep Flash away with ease.
Another reason is Strange is a pregog and automatically shield out a shield without having to actually think about doing it. The one second he lasts against Flash should give him enough time.
Also, his amulet is a very powerful weapon. A universal threat level weapon.
When Strange was attacked by a lightspeeder, his amulet, unbeknown st to Strange, fought like it was allove, jumped from his throat and blew him up. The eye moves at lightspeed when it does this. The eye can absorb infinite amount of energy, so that won't work.
Flash is weak against telepy, So there's that.
But really, worst case scenario: Flash knocks Strange's head off. Srange does his thing and go astral, making Flash unable to hurt him.
End
Strange would come back and reattach his own head.