You can get configure something pretty close to this already.
Settings -> Interface -> Unit Marker -> Individual Toggles -> check Scythe will cause a (local) marker to be placed whenever an enemy Scythe is revealed. Like all markers, you can either press the button next to it in chat, or F3 on the keyboard, to move the camera to that location.
From this menu, you can also cause markers to be placed whenever you spot Phantoms (the markers will stick around even after they cloak again, so you know where to sweep!), Athenas sneaking around, or even just structures of interest like Antinukes, Singularity Reactors, Big Berthas, Trinities, and Superweapons.