Be aware that there are several versions of Odoo, older ones do not have the API enabled off the shelve.
Also APIs may suffer issues when the volume of data exceed some amount. Then a sync strategy is required like Invantive’s one with @Eol.
We have a self-modified Odoo11 version.
We use a direct PostGres connection with a secured-by-restricted-IP port.
Then using the Invantive’s PostGres connector and [tables-replication-automation-with-stored-procedure-giving-statistics-error-handling-by-email] works like a charm.