In NavigationConfig.h there is:
TMap<FKey, EUINavigation> KeyEventRules;
is initialized in constructor: FNavigationConfig::FNavigationConfig()
KeyEventRules.Emplace(EKeys::Left, EUINavigation::Left);
KeyEventRules.Emplace(EKeys::Gamepad_DPad_Left, EUINavigation::Left);
KeyEventRules.Emplace(EKeys::Right, EUINavigation::Right);
KeyEventRules.Emplace(EKeys::Gamepad_DPad_Right, EUINavigation::Right);
KeyEventRules.Emplace(EKeys::Up, EUINavigation::Up);
KeyEventRules.Emplace(EKeys::Gamepad_DPad_Up, EUINavigation::Up);
KeyEventRules.Emplace(EKeys::Down, EUINavigation::Down);
KeyEventRules.Emplace(EKeys::Gamepad_DPad_Down, EUINavigation::Down);
Inside YourGameInstance.cpp
include “Framework/Application/NavigationConfig.h”
Inside UYourGameInstance::Init() function:
Super::Init();
auto NavConfig = FSlateApplication::Get().GetNavigationConfig();
NavConfig->KeyEventRules.Remove(EKeys::Gamepad_DPad_Left);
// the same with right, up, down