Sayyiduna Ibn Abbas (may Allah be pleased with them both) said: The Prophet (peace and blessings be upon him) used to say: "Whoever plunders is not one of us."
And he said: "There is no shighar (exchange marriage) in Islam." Shighar is that two women are married off in such a way that one of them is married in exchange for the other, without a dowry.
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 11958