f you are splitting the read/write queries to replicas, you need to guarantee strong data consistency. Else, Odoo will output errors. You may want to try out the Heimdall Proxy on the AWS Marketplace. It was specifically designed for Odoo applications to support 1) Strong consistency and 2) Queries in transactions. The Heimdall Proxy can support:
Automated Query caching
Read/Write splitting with ACID compliance
Connection Pooling
We have seen cache hit rates of over 90% with Odoo applications.