Did Jesus have Free Will? (Arianism) This is NOT this question

I've been reading a lot about Arianism and this is an interesting point that they have: 


  Arius believed the Son Jesus was capable of His own free will of right
  and wrong, and that "were He in the truest sense a son, He must have
  come after the Father, therefore the time obviously was when He was
  not, and hence He was a finite being,"[37] and was under God the
  Father. The Arians appealed to Scripture, quoting verses such as John
  14:28: "the Father is greater than I", and also Colossians 1:15:
  "Firstborn of all creation."


So then, before being on the cross, did Jesus (being 100% man) have free will to make mistakes?
It would be the heresy of monophysitism  (or, pushed to an extreme docetism)  to deny Jesus' free will.  

The classic text on the matter is in this matter is Luke 22:42 -


  "Father, if you are willing, take this cup from me; yet not my will, but yours be done."


If Jesus had no free will, this statement has no meaning.

Additionally, Hebrews 4:15 states:


  “For we do not have a high priest who is unable to sympathize with our weaknesses, but we have one who has been tempted in every way, just as we are—yet was without sin”


Again, if Jesus did not have the ability to sin, this statement makes no sense.

Finally, even Satan realized that Jesus could sin. Otherwise, why would he have even attempted to entice Jesus to break his fast, worship him, or put God to the test, in the wilderness in Luke 4 / Matthew 4?