Alright, lets get into this.
Gonna state right off the back, I'm pretty sure Fate has the AP Advantage here, seeing how Superman had the AP Advantage against Hulk, I know I'm using ABC Logic, but I think it works in terms of strength.
If Strange has the Time Stone, I feel like it'll be a little stomp-ish, but, suggesting that he doesn't I feel makes things more interesting.
Both can create Portals, so I feel like that eliminates Strange being able to BFR him in the Mirror Dimension, I feel like Soul Manipulation won't be much help here, as it's stated he needs energy. I feel like the biggest thing Strange has is Matter Manipulation, though I'm not sure if he would use it against fate, the only time he used it was giving Thor some beer.
Fate can increase his own magical gap, and further lengthen the AP Gap between the two, Transmuation would be of help here as Strange uses it often, being able to turn let's say a electric attack from Strange into butterflies or something. Duplication could work here too.
I'm going to have to go with Strange, I can only see Fate winning is if Strange continues to try and use basic magical spells and try to counter Fate blow for blow, without the use of Transmutation or Duplication, which would surely result in a loss due to Fate's superior AP.
Going with Strange via Transmutation and Duplication.
