The format that the custom Salesforce field with the API name My_Field_Name__c is transformed onto by default in Salesforce B2B Commerce is myFieldName. This is done to follow the JavaScript naming convention and to avoid conflicts with the standard Salesforce fields and relationships. The transformation rules are as follows:
Remove any namespace prefix from the field name, such as ccrz__ or cloudcraze__.
Remove any underscores from the field name and capitalize the first letter of each word after an underscore, such as MyFieldName.
Lowercase the first letter of the field name, such as myFieldName. Salesforce Reference: B2B Commerce and D2C Commerce Developer Guide, Query Transformation