Some of the gear of NPCs (non-player-controlled PlayerBase) doesn't seem to load in (naked body parts showing) under 1.21 Experimental until you get close within very roughly 20 meters.
This seems to be fixable by setting networkObjectBatchCompute and networkObjectBatchSend to -1 in serverDZ.cfg
No mods needed, it's enough to spawn one of the SurvivorM_* or SurvivorF_* characters (e.g. using CreateObject) and give them a full set of clothing (head/shirt/pants/boots/backpack/belt) via GetInventory().CreateInInventory(), there should be at least one of the clothing items that will not render in unless you get closer. I think players may also be affected as long as they don't move but have no way to confirm this currently.