This mod hasn’t been updated in 1 year and 7 months.
You can try editing info.json at your own risk to see if that fixes the issue.
Tested and confirmed working on Factorio 2.1.
I cannot guarantee that it will work for.
factorio>>mods>>Fusion_Atomic_Robots_4.1.0
info.json>>
"factorio_version":"2.0" → "factorio_version":"2.1"
"dependencies": ["base >= 2.0.0", "?space-age >= 2.0.0"], → "dependencies": ["base >= 2.1.0", "?space-age >= 2.0.0"],
If this workaround works for you, you may want to consider switching to an actively maintained alternative mod.
enjoy!! ;)