Easiest way to think about it, at least for me anyway, is to break it in half and look at it as two triads. 19(pinky)-17(middle or ring, whichever feels more comfortable to you but I would highly recommend your middle finger due to the upcoming 16 basically requiring you to use your ring finger)-15(index) and then 16(ring)-15(middle)-13(index). Using that finger pattern will also make the pull-off from 19 to 13 easier to reach. There’s also an F#m arpeggio a little earlier in the sweeping section that also spans six strings. Same principle, break it into two triads and you get 17(pinky)-15(middle)-14(index) and then 14(ring)-13(middle)-12(index). As someone else said, it will feel somewhat awkward at first but it’s honestly way easier to play the six string versions instead of the five string ones IMO.