Wolfram Function Repository (Under Development)
Instantuse addon functions for the Wolfram Language
Perform the intersection operation on multisets
ResourceFunction["MultisetIntersection"][list_{1},list_{2},…] gives a sorted list of the elements common to all the list_{i}. The number of occurances of each distinct element is the minimum of the counts in each of the list_{i}. 

ResourceFunction["MultisetIntersection"][assoc_{1},assoc_{2},…] gives an Association where the keys are the union of the keys in the associations assoc_{i} and the values are the minimum of the merged values. 
Find largest subsets of elements common to all the lists given:
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Multisets as Association of counts :
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If there is no intersection, the result is {}:
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If there is no intersection of the Association multisets, the result is <>:
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Compare to Intersection:
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