Get and Transform Excel files from SharePoint list

Thanks Edhans for your advice.

Luckily I was able to figure out how to achive my goal within Power BI.

Here is how to read the SharePoint list, extract attachments and combine them into one big table:

Top:

let
  Source = SharePoint.Contents("https://company.sharepoint.com/sites/SiteName/", [ApiVersion = 15]),
  Lists = Source{[Name = "Lists"]}[Content],
  #"Your Reports1" = Lists{[Name = "Your SP List"]}[Content],
  Attachments = #"Your Reports1"{[Name = "Attachments"]}[Content],

After this step, we have a column called "Content" that contains Table information of attachments.

Then use: Table.ExpandTableColumn to expand that table, give us the Content.Content with type Binary.

Then use: Table.ExpandTableColumn again on "Content.Content", give us "Data" column of each attachment

Then use: Table.ExpandTableColumn again on "Data" column to get combined table of data.

Along the way, Power BI generates "Transform File" "Sample File" functions automaticly.

Cheers!

Md