People in rich countries are (mostly) very nativist, so I doubt this kind of think would be popular. For whatever reason, people tend to value the lives of those in their country many times more than those in other countries.

So unfortunately, buying their labor at cheap rates seems to be the best way to transfer wealth right now, at least a big scale [0].

[0] - On a smaller scale individuals can donate to charities like Against Malaria Foundation or GiveDirectly, which I highly recommend everyone does if they have excess wealth.