Differential LC LPF and Impedance Matching Circuit
Any single ended passive filter can be made differential by mirroring it, in your case about the x axis.  Taking care to double or half the LCR components should they end up in series or parallel.

This is only useful if your driver and load are both differential.  Otherwise just ground on input (no current would flow in the other half of the filter).

Try a SPICE simulation to check your changes, e.g. LTSpice.