This resembles old CryBaby Wah-pedal. It had a sweepable band boost filter or more precisely a sweepable high-pass filter with some resonance boost. This is an active filter where the result is formed by a feedback loop that can be varied by turning a pot. This is not a bandpass filter that consists L1 and C2.
In pure math the order is the total number of reactive components (=inductors and capacitors in the signal and feedback paths. If 2 reactive components of the same type happen to be purely in series or parallel, they should be counted only as one.
In practice the most remarkable effect (here the wah) can be caused by a subcircuit. The others affect remarkably only at the ends of the frequency range. For example C1 only cuts some bass and makes a gap for DC.
The measures XXX desibels per octave or decade are not good for this. They are developed for easy comparisons between the steepnesses or selectivities between frequency selective filters. This filter is an equalizer, it's not for killing some frequencies.