*Drag and drop input.settings into Document\TheWitcher3*
Geralt
D-pad up now whistles for Roach
D-pad down now toggles HUD
Light and heavy attack disabled in exploration (Attacks are allowed once you enter combat state)
Disables Consumables outside of radial menu (Includes during combat)
Y/Triangle to mount Roach & Boats
Disabled dive up & dive down
X/Square to jump/climb
Right Trigger uses item
Right Shoulder casts sings
B/Circle to dive down

Roach
D-pad down now toggles HUD
Right bumper slows/stops roach
Right Trigger uses item
Disables sign use on roach
Y/Triangle to dismount roach
Y/Triangle to dismount boat
X/Square to jump

Install the mod Items in Radial Menu since the layout is exclusively based on using consumables while in radial menu

I recommend using the mod RDR Horse Controls together with these settings rather than the ones suggested on its mod page for a more accurate experience to Red Dead Redemption 2