Merge features from Table A using a field value to Table B if the Table A value matches one of a set of comma delimited values in a field in Table B

A have one dataset (Dataset A) that has contains fields, one of which is CityName; example value “Sudbury”. I have another dataset (Dataset B) that contains a field made up of comma delimited AltNames; example value “Gran Sudbury,Grand Sudbury,Sudbury, etc.

I need for these features to be joined in one dataset if the value in CityName matches any one of the comma delimited names in AltNames, however different records have different numbers of alternate names and it cannot match with a section of a comma delimited value. For example, Sudbury != Grand Sudbury.

I think that lists may solve this but I’m not familiar with the transformers that might enable this process.