Deuteronomy 22:5, 9-12 is concerned with mixtures of any kind.
A woman was not to put on a man's belongings, nor was a man to wear a woman's garment (v. 5a). Everyone who did these things was an abomination to Jehovah their God (v. 5b). The appearance of the brothers and sisters should be such that there is a clear distinction between male and female.
"You shall not sow your vineyard with two kinds of seed, lest the full produce, the seed which you sow, is forfeited to the sanctuary, as well as the increase of the vineyard" (v. 9). Literally, the Hebrew rendered "is forfeited to the sanctuary" means "be sanctified." Darby's note on this verse says, "Lit. 'hallowed,' or 'set apart to God,' i.e. appropriated to the sanctuary as a forfeit." If an Israelite sowed two kinds of seed in his vineyard, neither the produce of that seed nor the increase of the vineyard would be his. He was not allowed to keep them for himself. Instead, this produce and increase, having been forfeited, would be God's. This means that his labor in sowing his vineyard with two kinds of seed would be in vain.
I believe that the prohibition against sowing two kinds of seed in one's vineyard typifies the prohibition against teaching differently in the church (1 Tim. 1:3). The church is God's vineyard, and in this vineyard we should sow only one kind of seed, one kind of teaching. If we teach differently, sowing more than one kind of seed, the "produce" in the church will be forfeited.
An Israelite was not to plow with an ox and a donkey together (Deut. 22:10). This typifies the matter of becoming "unequally yoked with unbelievers" (2 Cor. 6:14a). "Unequally" means diversely, a difference in kind. According to Leviticus 11, an ox is a clean animal, but a donkey is unclean. In Deuteronomy 22:10 an ox typifies a believer and a donkey typifies an unbeliever. Believers and unbelievers are diverse peoples. They should not be yoked together because of the believers' divine nature and holy standing. This should be applied to all manner of intimate relationships between believers and unbelievers, including marriage and business. If a brother marries an unbelieving woman or if a sister marries an unbelieving man, there will be an unequal yoking of a believer and an unbeliever, and it will be difficult for them to live together. If a believer has an unbeliever as a business partner, the believer may have problems. For instance, the unbeliever may want to do certain things that are dishonest. As believers, we should not be unequally yoked with unbelievers, for this is a mixture, and every kind of mixture is abominable in the eyes of God.
An Israelite was not to wear clothing of mixed materials, of wool and linen together (v. 11). Wool comes from sheep, and linen is made from plants. God did not want the Israelites to mix these materials together.
An Israelite was to make twisted cords upon the four corners of his garment with which he covered himself (v. 12). The Hebrew word translated "corners" can also be rendered "edges." The requirement here may refer to what is mentioned in Numbers 15:38. "Speak to the sons of Israel, and tell them to make tassels on the corners of their garments throughout their generations, and to put upon the tassel of each corner a cord of blue." In this verse "cord" signifies binding, and "blue" signifies something heavenly; hence a blue cord indicates a heavenly binding. For us today, this cord of blue signifies that, as children of God, our conduct and behavior should be beautiful and should be under the binding of the heavenly government.