Actually since my name's been mentioned here and there, I might as well give my opinion on the fight.
Wanda wins.
Why?
1. Because Wanda can survive Universal explosions at ground zero with zero damage.
So that gets the "Reflex" issue out the way.
Ground Zero:
Wanda explodes the Universe in her face
Boom boom bang, where's Wanda after this?
In some village shopping
I've NEVER seen Jean as DP or as WPOTC even taking a Universal explosion let alone surviving it.
2. Because Wanda is immortal and Jean is definitely NOT.
Hawkeye drove an arrow straight into Wanda's heart
Notice the arrows Position, right on the side of the Heart,
Hawkeye came to KILL, READ the scan.
ONE Panel later, Everything is as was.
"If I couldn't KILL you"......
As for Phoenix, Kill the Avatar, you win the fight.
WHY?
Because the Phoenix Force is UNAWARE of it's one Existence in it's Natural State (without Avatar)
IN FACT
The Phoenix Force has NO CONSCIOUSNESS in it's Natural State
So WPOTC CAN'T Hurt Wanda physically, because Wanda can take a Universe blowing up in her face, and Jean has NEVER been depicted On Panel as being able to output Power that can destroy a Universe.
Lastly, since Jean can't affect Wanda physically, in Power generation Wanda is greater too.
3. Because Wanda can destroy and Re-create Eternity (REALITY 616) on a passing Whim.
"She's starting to REMAKE Reality 616... again"
"Who knows how she'll change Everything this time"
Yes, EVERYTHING in the 616 REALITY (ETERNITY)
And we ALL know Jean has NEVER destroyed, remade or created a Universe On Panel.
Wanda 10/10