Well, I’m in the same country, less than 200km from our host. I play on ~70 latency (shown by the game). I see this phenomenon on a regular basis.
I’m pretty sure this issue didn’t exist in the first couple months (year). They obviously changed something, probably to improve performance, the game not rendering stuff that doesn’t HAVE TO BE SEEN by any player (or host) and then it spilled over, wouldn’t be the first time…
Edit: This issue remained after I got better internet connection and upgraded router and firmware.
If I recall, the “freezer” system was mentioned as a performance uplift that came with Shadows over Bogenhafen.
Patch 1.2 “Horde enemy pooling. Resurrect dead enemy units and put them in a freezebox to be reused instead of spawning new ones when spawning a large amount of enemies during hordes. Improves CPU performance during horde events.”
Could have been expanded to despawning units far away.
I’ve experienced it a lot since then, but the only evidence I have is almost 2 years ago but it’s a CW appearing out of thin air on host: Here
Well the CW who is up on the platform on Horn of Magnus barrel drop event is almost always invisible for me until I get past the corner of the wall and closer to the little flight of stairs before he appears.