It seems it should be totally mutar to do a Pidyon HaBen on Zoom because many Acharonim say that shelichut can work (Rav Yosef Zvi Rimon says as much). That said, I have a family that wants the kohen to be someone they know who lives in Israel (in some ways, taking advantage of the Zoom situation!). The kohen happens to currently be in America, but in a few days is going back to Israel. May they send him the coins (or something worth that amount) now while he is in America with the intention that he doesn’t yet make a kinyan on the coins, and has the kavanah that they don’t yet belong to him. He would officially make a kinyan the day of the pidyon while on Zoom (when he will already be back in Israel). Advantage of this would be that it’s logistically easier than finding a shaliach in Israel, sending them something, etc.
Yes, that works. The father should say that he would like the kohen to hold onto these coins for him. Then, over Zoom on the right day, say that he is makneh the coins to the kohen, and the kohen can then raise them up with the intent of being koneh them.