What is the reason why the noise node can’t be used here?
Field sockets can’t be plugged into non-field sockets (diamond to cirlce). The best way (that I know of) to get that to work is to put it through an attribute statistic node and plug in the mean. There might be a better way that someone else knows about.
The transform node doesn’t take field inputs because it’s supposed to work with all kinds of data (not just meshes), but you can use a set position node instead.