You don't want a loop here anyway, just an If:
if(LStick="Down" | LStick="DownRight" | LStick="DownLeft") -> IsCrouching= "True" Else IsCrouching= "False"
In C2, use Compare two values:
First value: LStick="Down" | LStick="DownRight" | LStick="DownLeft"
Comparison: Equal to
Second value: 1