Hi Alex,
For material , only Enterprise Search (ES) can be used as the search mode for duplicate check so no fuzzy search(BAS-AD) as search mode for duplicate check for material is supported.We are currently working on HANA Search(HA) for material which will be part of MDG 7.0 SP02 release.
So as mentioned by Riccardo Enterprise Search (ES mode) does not currently support weights/ranking, so overall in material duplicate check ,weights/ranking is not supported.
Thanks & Regards,
Ibrahim.