Looks getting error due to incorrect association path.
Please try with similar given below.
[Item_Stock_Location/Stock_Location/Country = $SelectedCountry]
[Item_Location/Location/Location_Stock_Location/Stock_Location/Country = $SelectedCountry]
[Item_Stock/Stock/Stock_Stock_Location/Stock_Location/Country = $SelectedCountry]
Hello,
Country attribute is an enumeration, so it must be compared with an enumeration of same type not with the path. The first part of your expression is fine change the second part to $Selected_Country_Filter/Country (I am assuming you have this $Selected_Country_Filter this object on the page) or $currentObject/Country.
Hope this helps!
Thanks & Regards,
Amit Gupta