MarlinKimbra support 4 extruder width different Step /mm, feedrate, acceleration, retraction acceleration, ejerk:
#define DEFAULT_AXIS_STEPS_PER_UNIT {160,160,160,451,625,625,625}
#define DEFAULT_MAX_FEEDRATE {3000,3000,3000,45,100,100,100}
#define DEFAULT_MAX_ACCELERATION {1000,1000,1000,1000,3000,3000,3000}
#define DEFAULT_RETRACT_ACCELERATION {10000,10000,10000,10000}
#define DEFAULT_XYJERK 20
#define DEFAULT_ZJERK 0.4
#define DEFAULT_EJERK {5,5,5,5}