My read business query works fine on 10k business entities for 1 single client. 1 business entity is a complex structure which involves tens of nodes and relationships.
In case I'd like to have the same performance for the query for 10 concurrent clients- in case I'll move to AuraDB managed solution and introduce 10 read-replicas, will I achieve the goal?
Aura doesn't support read replicas (yet) but it has cluster setup so you get at least 3 core-members to serve reads.
But you can either create one aura instance per business client, or optimize your query or use self-managed (e.g. with a startup license) and setup a cluster with read-replicas there.