COUNTIFS With two column

You may want to try in a calculated column,

RESULT_CC = 
IF(
    COUNTROWS(
        FILTER(
            DS,
            DS[Item] = EARLIER( DS[Item] )
                && CONTAINSSTRING( DS[Country & Code], SUBSTITUTE( EARLIER( DS[Country & Code] ), "-LL", "" ) )
        )
    ) > 1,
    "Yes",
    "No"
)

I personally prefer solutions in PQ and Excel, considering that DAX is not so competent in coping with string transformation.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("Xc0xDoAgDIXhu3TG5AlFymiiGxNxI9z/GhJMVRj/L31pKbRaR4aOMyGAqhlhSelnebfA3HrCfmt0ZTjMrSdB4kOMsb22aH8T0YlSlMC+f2e8r5ztgtik3g==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Item = _t, #"Country & Code" = _t]),
    Custom1 = let cols = {"Item", "Country & Code"} in Table.RemoveColumns(Table.Group(Source, cols, {"ar", each _}, 0, (x,y) => Number.From(not(x[Item]=y[Item] and Text.Contains(Text.Replace(y[#"Country & Code"], "-LL", ""), Text.Replace(x[#"Country & Code"], "-LL", ""))))), cols),
    Custom2 = Table.TransformColumns(Custom1, {"ar", each Table.AddColumn(_, "RESULT_PQ", (x) => if Table.RowCount(_)>1 then "YES" else "NO")}),
    #"Expanded ar" = Table.ExpandTableColumn(Custom2, "ar", {"Item", "Country & Code", "RESULT_PQ"}, {"Item", "Country & Code", "RESULT_PQ"})
in
    #"Expanded ar"

Still, Excel formula, our oldie but goodie, does the trick with ease; the DAX calculated column solution is, to some extent, a verbose copy of it!

=IF(COUNTIFS([Item],[@Item],[Country & Code],SUBSTITUTE([@[Country & Code]],"-LL","")&"*")>1,"YES","NO")