Hi there,
I realized that when I have the axes set to a certain value (local, parent, world), and copy a key, when I paste it, it pastes it as local always.
E.g. a bone x position in world axis is 2000, I copy it, and then I paste it at another time position where the root was moved 200 pixels: then the pasted value is 2200, because it pasted relative to the parent/ locally.
So instead I need to select and copy the 2000 value text directly, and paste it manually, to have the 2000 x value pasted correctly relative to the world axis. So I cannot copy paste both x and y at once on world axis, and it makes it clumsy to have to select the numeric value each time.
My suggestion is that whenever you copy a transform, scale, etc. key, it copies the values according to the currently selected axis, to allow for flexible and fast usage.