The Chinese really love putting AAMs on everything.
It is certainly an interesting idea to add AA compabilities to UCAVs, but it feels like a very niche capability.
A WL or CH is most certainly not going to win any dogfights, so this capability is probably only ever be useful against helicopters or other UAVs.
Does the TL2 or TY90 have LOAL and/or HMS assisted off-boresight aiming capabilities?
If so, that would potentially change the game a little, but if not, it might be more useful to integrate something like the PL10 onto these UCAVs as well/instead.
Introduce an auto tracking capability to the optics turret(software only should be enough) and you will have something that will give even manned fighters something to think about.
But I suspect the main target for these AAMs would be other UAVs. Iran’s recent alleged incursions into Israeli airspace with UAVs would be a good example.
With long endurance, it would be possible to maintain 24/7 overlapping boarder patrols to guard against infiltrating hostile UAVs without putting any strain on your fastjet and attack helicopter fleets.
Throw in some of the radar equip UAVs China is also developing, and you have the core parts of a semi-automates air policing force.
If they really wanted to, they could potentially also integrate some of the anti-drone rifle-jammers or even destructive lasers onto the UCAVs to allow them to counter even smaller UAVs. Although detection would be the main technical challenge against those smaller drones.
If it is the Saudis/Saudi allies who ordered the WL2, it might only be a matter of time before one of them scores the first operational UCAV AA kill in and around Syria against an Iranian drone or Syria helicopter.