Is it forbidden for a father to marry the daughters of a foreign woman who breastfed with his own daughter from their mother, or to marry his own daughter who was breastfed by a foreign wife?

What is unlawful by blood relation is also unlawful by fosterage. The prohibited relations by blood are mentioned in the Almighty's saying: "Prohibited to you are your mothers, your daughters, your sisters, your paternal aunts, your maternal aunts, your brother’s daughters, your sister’s daughters, your foster mothers who suckled you, your foster sisters, your wives’ mothers, your stepdaughters under your guardianship, born of your wives to whom you have gone in—but if you have not gone in unto them, there is no sin upon you [to marry their daughters]—and the wives of your sons who are from your own loins, and that you take [in marriage] two sisters simultaneously, except what has already occurred. Indeed, Allah is Ever-Forgiving, Most Merciful."

Accordingly, your foster daughter's sisters are not unlawful for you.