A. Add the Journey Membership Lightning component from the Marketing Cloud Connect Managed Package to the Contact Page Layout.

B. Schedule a batch job in Salesforce to query Marketing Cloud for the contact membership status of all contacts in Journeys on a regular basis (for example, once per hour) and write this to the Contact record.

C. Develop a custom Lightning web component in Salesforce to query Marketing Cloud in real time to get Contact Journey membership.

D. Create a multi-select picklist on the contact record, and use the out-of-the-box Contact Update activities in Journey Builder to add or remove the name of the journey as they enter and exit.