Im working through a similar issue. Im recommending we use ANSI here (I have been using that same document that you attached).
We plan to use EDI and i want to make sure that we dont have any trouble in the future. Epicor UOMs are too difficult to change once you have a part tran record.
So far I only have seen that EDI may be affected. I am curious if other things like Configurator or other Modules could be affected.
Even Labels in the AIAG Standard recommend ANSI, because General Motors, FORD etc… Scan them. Sometimes they have a PDF Barcode (QR type) which embeds the UOM with the Qty.
I dont think Epicor modules would be effected. When we built a configuration in the past, parts were using IUMs associated with that part and that are in the UOM tables.
Definitely could impact some things that commerce connect uses though.
Another one I can probably think of is Insite Manifest… After all it communicates with Shipping API’s. Fedex, UPS, USPS… I assume they have some requirements for UOMs, especially if one ever ships Hazmat then UOM is Required (per ANSI Std)