In my organization we are trying to use Asana a sole system to manage all of our tasks.
We are now able to send emails from clients directly to Asana as tasks (by forwarding emails to Asana), but we need to know if following emails from the same sender or the same subject, can be sent as subtasks. This would allow us to have better organized our projects and provide follow up instead of having a new tasks for follow up emails.
According to me, this is not possible. Forwarded emails become tasks in a given project, there is no way to make them become subtasks, unless you have another automation on top of it, for example using make.com or Zapier.
It does not answer your question, but did you consider not forwarding emails? I know I don’t anymore, because it just moves the mess elsewhere. I don’t want to have to re-read an entire email in Asana. What I do is find or create the relevant task, and write a few words about what was said. Usually a long email can be summed up with a few words…