Quick answer: Godot 4 MultiplayerSpawner using config defaults instead of per-instance properties? Config replaces; doesn't merge - assign per-instance via spawn data.
Spawn enemies with different stats; all spawn with default stats.
Pass via spawn function
spawn(data) where data includes per-instance config. Spawner applies via your function.
Or post-spawn customize
Spawn defaults; then call set_stat. Two-step; works.
Use multiple spawners
One per enemy type. Per-spawner defaults; less interaction.
“Spawn config is the template. Per-instance variation needs explicit data.”
If your spawned actors all look the same, the per-instance data flow is the bug. Document the spawn data structure.