Hi @Gema_Leiro you can use Unito to keep both systems in parallel and in sync (so as to not force everyone off their favorite tool), do a rolling migration (progressively move over), or a one-time migration. Note however that while we’ll link attachments across, we won’t download and re-upload file attachments between tools (but neither will the CSV import or Zapier).
Also, Zapier is event triggered so isn’t as practical for migrations.
Just try it, there’s a 14 day trial: https://unito.io/sync/asana/jira/
Marc @ Unito