The details of Israel's journey through and away from Seir are not clearly specified. There is vagueness in the words describing Israel's departure away from our brothers...away from the Arabah road from Elath and Ezion-geber.
The important point is that Israel is now advancing under the leadership of the Lord.
The second part of this verse marks the next stage in Israel's journey, namely, the approach to Moab.
8 Nous passâmes à distance de nos frères, les enfants d'Esaü, qui habitent en Séir, et à distance du chemin de la plaine, d'Elath et d'Etsjon-Guéber, puis nous nous tournâmes, et nous prîmes la direction du désert de Moab.