I think the idea of less flaps if you're expecting wind-shear is to increase your approach speed. With a higher approach speed, any wind-shear will be a lower percentage of your airspeed, and will have less effect on you. At least, I think that's the theory! Never experienced any really bad wind-shear myself yet - the mild stuff I have experienced is no problem if you're expecting it, but a bit scary if you're not.
PPPPP - the de-crabbing technique will come with practice, don't worry! Out of interest, has your instructor taught you the wing-down method? Everyone's different, but I personally find it much easier than de-crabbing. If you haven't been shown it, then ask your instructor to demonstrate the next time you're flying in a cross-wind. Try both methods, and use whichever one you find easiest!
FFF
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