There is no feature like that on pgc. The problem is that that groundspeeks API does not provide an fast method to get all TB:s in an arear etc. Each cache has to be updated idividually and with the speed pgc can do that the information about TB:s will almost always be out of date.
There is one way to do that on gc.com. Create a PQ with your area and use the optione "Have Travel Bugs". You can now use the pq preview function on gc.com maps to show caches with TB:s.
Ofcource the information might be out of date if someone that have picked up a TB has not logged it online and the same for TB drops