Here comes another one..
The old Portable fusion reactor in 1.1, used to be turned into a portable fission reactor by the mod and consumed Shielded nuclear fuel cells.
Now in 2.0 the old portable fusion reactors were replaced by actual portable fission reactors and newer powerful portable fusion reactors were introduced.
The Mod now makes these new powerful portable fusion reactors consume this mods Shielded Nuclear fuel cell, instead of the obviously better fitting new portable fission reactors.
If you may swap them...