Attaching outdoor Ethernet cable to stucco?
The stucco clips linked in the question should be OK, as long as they are big enough that they don't damage the cable.  

Flex Clips are popular with the cable companies 



you drill and use a plastic anchor with these



It is going to sag a bit between anchors, but the closer you space them, the less it will sag.  

Gluing it would be a mess - I would not recommend that.