According to the Porvoo Declaration the Porvoo churches “welcome persons episcopally ordained in any of our churches to the office of bishop, priest or deacon to serve, by invitation and in accordance with any regulations which may from time to time be in force, in that ministry in the receiving church without re-ordination.”
What is needed for a pastor to work in another Porvoo Church?
First you need to see if there is job available. You may have found that out already or you may need to ask via the Porvoo Contact Person in the other churches. Regarding qualifications you can read the Commentary on the Porvoo Declaration. You will always need a letter of recomendation from your bishop. Requirements such as knowledge of local language might also apply.
The Peter Fjellstedt Foundation in Sweden has had courses that can prepare Luterhan pastors for service in the Anglican tradition and vice versa.