Yes you would still have access to the DLC content. What you will not have access to is the season pass content since that is account based. Keep in mind that in order to switch which platform account is designated as the primary in your cross save setup, you will have to wait the 90 days from the time you first disable it to the time that you are able to to re-do cross save with a new primary account. I would also point out that by switching accounts, you will be reverted back to the state that the characters from the new primary account were at when you initially setting up cross save. Meaning all progression as well as the gear that you have acquired over the course of your active cross save setup would be "lost" since it is tied to the platform account that was the prior primary before making the switch.