This question is related to that question: Why is Linux choosing the wrong source ip address
Setting a src ip for a static route on client may be okay for one time or if just needed. However in a network of many clients which may even be not under full control this may not be an acceptable workaround. Is there a standardized protocol which allows to deploy routes together with source addresses to clients automatically?
For Next-Hop's i know there exists a DHCPv6-option for (Source: https://www.isc.org/blogs/routing-configuration-over-dhcpv6-2/ ) but this seems not to cover the source address.