You absolutely can make wrist warmers like that. I think there is a pattern like that in Weekend Knitting by Melanie Falick.
You can choose any yarn you want, any pattern and as long as you get the right gauge for your measurements, knit up a rectangle and seam it together, leaving an opening for the thumb.
Just remember that the width of your wrist and that of your hand at the widest part at the base of your thumb is ver different so you want enough stretch to keep you warmers from slipping down over your hands.
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