Are you sure? The Democratic Party of Luxembourg and the Reformist Movement-Open Flemish Liberals and Democrats are liberal...
I thought the DP in Luxembourg were in opposition for some reason, but none the less, they're more Center Right than Liberal.
In Belgium of the current coalition the NVA, MR and OVLD are 'Liberal Conservative', meaning Right of Center and only liberal in the sense that they're economically liberal and socially centrist and/or don't focus on social issues.
Yes, it can pass decrees (though not laws, because there is no Parliament to pass them).
In which case I don't consider it a government in the sense of a political grouping that can pass legislation but rather the state apparatus continuing to run in between governments.