Bamboo Cotton yarn: can't recommend this yarn enough! Soft, yet sturdy. And won't look fuzzy after wearing and washing it. For this yarn, I personally like the yarn weight category 5, but you can go a little chunkier or thinner depending on the sweater you are embroidering and the look you want to go for. Be sure to check out all the color options!
Anti-Pilling Yarn: any anti-pilling yarn is great for embroidering on sweaters because, like the yarn says, it won't pill! I especially like using an anti-pill yarn made from bamboo because it is so soft. An option linked here.
