In 5.9, a new Asset match configuration is introduced.
Basic configurations for Asset match
The simplest configuration is upload only with no metadata and Asset match strategy: No matches. In this case Match metafield is Relative path - Fullpath UNC (must be the same as what is in Stamp field).
If you have an asset in MM with Fullpath UNC like this and it is unique
if you import file with name File1.png it will have the same Fullpath UNC.
So it will match and replace Asset in MM.
Upload with metadata from sheets. Match metafield Fullpath UNC. MatchTokenColumn must in this case be the same as FileNameColumn.
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