You cannot pass dynamic arguments, but you can pass constants. You can use template functions if you like, but I prefer this method. You can do all of this in the CPP which means no extra function declarations.
DECLARE_DELEGATE_OneParam(FCustomInputDelegate, const bool);
InputComponent->BindAction<FCustomInputDelegate>("OnSomeInput", IE_Pressed, this, &AMyActor::OnInput, true);
DECLARE_DELEGATE_TwoParams(FAnotherCustomInputDelegate, const bool, const float);
InputComponent->BindAction<FAnotherCustomInputDelegate>("OnSomeOtherInput", IE_Pressed, this, &AMyActor::OnOtherInput, true, 10.f);
You can pass as many params as you like, you just need to declare a different delegate type.