использование:
=ARRAYFORMULA(IF(COUNTIF(IFERROR(IFNA(REGEXEXTRACT(INDEX(SPLIT(
REGEXREPLACE(A:A, "https?://www.|https?://|www.", ), "/"),,1),
"\.(.+\..+)"), INDEX(SPLIT(
REGEXREPLACE(A:A, "https?://www.|https?://|www.", ), "/"),,1))),
IFERROR(IFNA(REGEXEXTRACT(INDEX(SPLIT(
REGEXREPLACE(A:A, "https?://www.|https?://|www.", ), "/"),,1),
"\.(.+\..+)"), INDEX(SPLIT(
REGEXREPLACE(A:A, "https?://www.|https?://|www.", ), "/"),,1))))>1,
"Duplicate", ))