Need to apend data from folder, in case some files have column names in other language

hello, I went through the steps,which were created automatically during connection and expanding the tables and I could not find the moment when the headers have been added. the first step after expanding the table already has headers. Below I have copied the M text. I do not know M, it was created automatically, but maybe it could help to understand what I have done.

let
    Source = Folder.Files("R:\Materials\External warehouse\Адмирал\WH backup morning stock"),
    #"Removed Other Columns" = Table.SelectColumns(Source,{"Content", "Name"}),
    #"Extracted Text Before Delimiter" = Table.TransformColumns(#"Removed Other Columns", {{"Name", each Text.BeforeDelimiter(_, ".xls"), type text}}),
    #"Changed Type" = Table.TransformColumnTypes(#"Extracted Text Before Delimiter",{{"Name", type date}}),
    #"Filtered Hidden Files1" = Table.SelectRows(#"Changed Type", each [Attributes]?[Hidden]? <> true),
    #"Invoke Custom Function1" = Table.AddColumn(#"Filtered Hidden Files1", "Transform File from WH backup morning stock", each #"Transform File from WH backup morning stock"([Content])),
    #"Removed Columns" = Table.RemoveColumns(#"Invoke Custom Function1",{"Content"}),
    #"Expanded Table Column1" = Table.ExpandTableColumn(#"Removed Columns", "Transform File from WH backup morning stock", Table.ColumnNames(#"Transform File from WH backup morning stock"(#"Sample File (2)"))),
    #"Renamed Columns" = Table.RenameColumns(#"Expanded Table Column1",{{"Name", "date"}}),
    #"Changed Type2" = Table.TransformColumnTypes(#"Renamed Columns",{{"Материал", type text}, {"Описание материала", type text}, {"Batch", type text}, {"Storage Type", type text}, {"Storage Bin", type text}, {"Storage Unit Type", type text}, {"Storage Unit", type text}, {"Stock Category", type text}, {"Завод", type text}, {"Available stock", type number}, {"Base Unit of Measure", type text}, {"Storage Location", type text}, {"SLED/BBD", type date}}),
    #"Renamed Columns1" = Table.RenameColumns(#"Changed Type2",{{"Base Unit of Measure", "UoM"}, {"Storage Unit Type", "Pal Type"}}),
    #"Inserted First Characters" = Table.AddColumn(#"Renamed Columns1", "Start3", each Text.Start([Описание материала], 3), type text),
    #"Added Conditional Column" = Table.AddColumn(#"Inserted First Characters", "material type", each if [Материал] = null then "load issue" else if Text.StartsWith([Материал], "5") then "Pack" else if Text.StartsWith([Материал], "9") then "Pack" else if Text.StartsWith([Материал], "3") then "Ingred" else if Text.StartsWith([Материал], "4") then "FG" else if [Start3] = "WRC" then "WRC" else if [Start3] = "CTD" then "WIP" else if Text.StartsWith([Start3], "TM") then "Trim" else if [Start3] = "SHT" then "WIP" else "Ingred"),
    #"Renamed Columns2" = Table.RenameColumns(#"Added Conditional Column",{{"Start3", "Type"}})
in
    #"Renamed Columns2"

--------------------

I have only 3 bilingual columns, which I would like Power Query to understand automatically as one column name:

Material = Материал

Material description = Описание Материала

Plant = Завод