How to create a host on a DigitalOcean team with Terraform?
According to the article you linked, Team Resources are shared. This means that all droplets (hosts) are shared across the team once you have a team in place.

source: https://www.digitalocean.com/community/tutorials/how-to-use-teams-on-digitalocean#team-resources

This means that each team member, using his own personal token, can manage all the resources shared with her. Terraform allows each user to use his own credentials when managing resources, and includes a state file (that must be shared as well). Managing shared tfstate and managing secrets is addressed in this DevOps.SE question.