Praise be to Allah.
It is permissible for the poor person to appoint the rich person to receive zakaah from himself and keep it for him, so that it stays with the rich person, so that the poor person can take it whenever he wishes.
Al-‘Allaamah Ibn ‘Abd ar-Rahmaan ibn Qaasim said in Haashiyat ar-Rawd (3/293): In order for it to be valid and for the poor person to be regarded as having taken possession of it, it is stipulated that he should receive it, and it is not valid for him to dispose of it before that.
If the poor person appoints the owner of the wealth to receive it from himself and buy a garment and the like with it after that, that is valid. End quote.
Shaykh Ibn ‘Uthaymeen (may Allah have mercy on him) said: It is not permissible for a person to buy specific items with his zakaah and give them instead of cash. They said: That is because cash is more beneficial to the poor person, because cash may be disposed of however he wishes, unlike specific goods, for he may have no need of them, in which case he will be forced to sell them at a lower price.
But there is another way, if you fear that if you give zakaah to this household, they will spend it on things that they do not need. In that case, you may say to the head of the household – whether that is the father, the mother, the brother or the paternal uncle: I have zakaah; what things do you need, so that I can buy them for you and send them to you? If he does it in this way, then that is permissible, and the zakaah will be given in an appropriate way.
End quote from Majmoo‘ Fataawa Ibn ‘Uthaymeen (18/481).
This comes under the heading of the poor person appointing the giver of the zakaah to buy things with the zakaah funds, not only to receive them on his behalf, but it implies that he receives them from himself first, even if the poor man or the giver of the zakaah does not state that clearly.
And Allah knows best.