I would like to use Trigger Ready Flows - whenever Status updates from A to B on a case, The Case Owner will be auto-added as a Member on the Case Team. I know that this is possible with a trigger but I would like to use point /click customisation if possible. Any ideas on how this could be completed with Flow /Process Builder?
Just going to repeat my comment since I believe this does answer your question. I just looked at my Flow sObjects and caseTeamMember is there, screenshot. You should have no troubles building what you need with Process Builder and/or Flow.