Hiya,
Nothing out of the box as such (apart from; see below), and it heavily depends on if you got the info required in the model. If you pop long/lat/height into the properties of your model, things become a bit easier. If you can’t, you can always traverse all the tiles in the tileset, as each of them have a bounding circle which you can use, depending what is in the tile in question (sometimes it’s one building, other times it might be many). The resolution of this kind of meta data will be the key to what you’re trying to do.
But if you do have that info, the rest is “easy”; distance between pins are done through simple math or the Cesium.Cartesian3.distance, including direct line vs. over the globe ellipse. More on all of that here;
After that it’s all about writing those style rules around sitance between the pins and your coords / bounding coords, and update accordingly. If the pins move, update the style on the move, or if they move all the time, pop them into a cycle every X seconds. Let me know if you want some specifics about something in this bucket of stuff.
Cheers,
Alex