they are defined in the Reshade.ini file. you can change the keycode there.
INPUT]
ForceShortcutModifiers=1
InputProcessing=2
KeyEffects=35,0,0,0
KeyNextPreset=0,0,0,0
KeyOverlay=36,0,0,0
KeyPerformanceMode=0,0,0,0
KeyPreviousPreset=0,0,0,0
KeyReload=0,0,0,0
KeyScreenshot=44,0,0,0
Pretty sure reshade also allows you to redefine keybinds from within the UI menu