let
    Source = Excel.CurrentWorkbook(){[Name="Таблица1"]}[Content],
    subst = Excel.CurrentWorkbook(){[Name="Таблица2"]}[Content],
    join = Table.Join(Source, {"Столбец2"}, subst, {"Что"}, JoinKind.LeftOuter),
    addTemp = Table.AddColumn(join, "temp", each if [НаЧто] <> null then [НаЧто] else [Столбец2]),
    delOldCol2 = Table.RemoveColumns(addTemp, {"Столбец2"}),
    renToNewCol2 = Table.RenameColumns(delOldCol2, {"temp", "Столбец2"}),
    result = Table.SelectColumns(renToNewCol2, Table.ColumnNames(Source))
in
    result

let
    Source = Web.Contents("http://194.186.103.234:27705/api/v1/yml/file_standard",
        [
        Headers = [
            #"Accept" = "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9",
            #"Accept-Encoding" = "gzip, deflate",
            #"Accept-Language" = "ru,en;q=0.9",
            #"Connection" = "keep-alive",
            #"Upgrade-Insecure-Requests" = "1",
            #"User-Agent" = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.116 YaBrowser/20.7.3.100 Yowser/2.5 Safari/537.36"
        ]]
    ),
    toXml = Xml.Tables(Source)
in
    toXml

=AVERAGEIF({'Файл1'!C2; 'Файл2'!C2; 'Файл3'!C2; 'Файл4'!C2}; ">0")

"(" & Text.Combine(lastMaleExts, "|") & ")[^а-я]?"

let
    lastMaleExts = {"[ыи]х", "[оа]в", "[ыи]н"},
    rexExpContains = (string, pattern) =>
    Web.Page(
        "<script>
            var regExp = /" & pattern & "/i;
            document.write(regExp.test('" & string & "'));
        </script>")[Data]{0}[Children]{0}[Children]{1}[Text]{0},
        p = "(" & Text.Combine(lastMaleExts, "|") & ")[^а-я]",
    test = rexExpContains("петров булкас", "(" & Text.Combine(lastMaleExts, "|") & ")[^а-я]")
in
    test