Not Flamenco, I mean more along the lines of Santana style. Cos he basically plays blues, but somehow it sounds Latin - is it the Mixolydian?

It's not just the solo. It's also everything behind the solo that gives it the feel. The instrumentation might be a factor. Play around with some Santana and it might gives you an idea of how he makes his music.
Try Dorian.

Carlos Santana used in almost every song he ever recorded.
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Santana doesn't use dorian as much as people think and I've never heard him play anything phrygian. He uses the entire natural minor scale, though, rather than the minor pentatonic; that gives him the Latin sound, along with the associated background chords (derived from the minor scale) and percussion.
I'm pretty sure you need more than just a scale to get a desired feel.
Yep, as everyone else said, it's the backing that gives anything the sound.
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santana by himself doesnt sound to latin but the latin beats and back up give it that latin feel, you could learn some flamenco solos and mess around with that
Seems like a lot of extended chords, and the licks are rather short and staccato.
It has almost nothing to do with which scale you pick

It's in the way you phrase your solos, the techniques you use, your tone and the notes you pick. Scales have very little to do with it.

The easiest way is to listen to his solos and try to copy him rhthymically. You don't need "modes," simple major/minor scales will suffice.
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[U]        |/     .-.              [/U]
[U]       /|_     `-’       |      [/U]
[U]      //| \      |       |      [/U]
[U]     | \|_ |     |     .-|      [/U]
      *-|-*    (_)     `-’
Hmm, Santana's licks and phrasing doesn't sound so "latin" (which I guess means mexican, reggaeton, or central american music, instead or south american "rhythm" or "cumbia" music), but the whole track behind it does sound...

Percussion has a leading role in making it sound "latin".
Like in "Corazon Espinado", you can hear the matracas and stuff in the background.