If you create separate ACBC questionnaires, it may make it impossible to properly combine the data if you want to create a single market simulator. You would be left to analyzing the results separately for your multiple projects. But, on the other hand, perhaps such an analysis would answer the business questions at hand.
ACBC has the ability to create "constructed lists" (also known as "dynamic lists") for attributes like brand within a single ACBC questionnaire. So, one approach is ask respondents ahead of time which brands are applicable to them, moving only the applicable brands forward into the conjoint exercise. That keeps all the analysis in one data file. If doing this, you must tell ACBC-HB utility estimation how to treat the levels that are dropped for each respondent.
There are many questions about what you're trying to accomplish. I'd recommend you take these questions up with a consultant or perhaps try asking additional questions here or asking them of our technical support team.