Using the Korg padKontrol as a sustain pedal (or other functions)
Alesis VI49 USB Keyboard Controller w/ Sustain Pedal Bundle - Pixel Pro Audio
Hfsecurity Usb Double Foot Switch Pedal Control Keyboard Mouse Plastic Nonslip Metal Momentary Electric Power Foot Pedal Switch - Keyboards - AliExpress
StudioLogic VFP1/10 Piano Style Sustain Pedal VFP-1-10 B&H Photo
USB Transcription Foot Pedal | Dictation Foot Pedal
Cheap Electronic Digital USB 7 Pads Roll up Set Silicone Electric Drum Kit with Drumsticks & Sustain Pedal | Joom
Photo Savings MA99005307500 M-Audio USB Midisport Uno Portable 1x1 USB MIDI Interface for Mac & PC and Deluxe Accessory Bundle w/ Keyboard Sustain Pedal, Ad