Is it permissible not to visit relatives during Ramadan due to financial hardship and the inability to buy gifts, knowing that going without a gift is unacceptable in the place of residence, and buying them would lead to borrowing and usury?

It is not permissible to borrow from an usurious bank except in cases of dire necessity. If a loan was previously taken from an usurious bank, repentance to Allah is obligatory, because usury is a war with Allah and His Messenger, a barrier to success, and one of the seven destructive sins. Allah does not burden a soul beyond its capacity regarding kinship ties. Visiting can be replaced by calling or messaging if going without a gift is not feasible.