We have two software gateways (on Linux) for IPv6 that take fullviews from ISPs and announce our AS. And several nodes connected to Internet via the gateways. Something like at picture:

And we would like to organize loadbalicing of outgoing traffic on network level. So one node sends packets via first gateway another node sends via second one.

Is there any native IPv6 feature for this that makes nodes to chose gateway automatically (perfectly if route will be chosen for each new connection) and may consider failing of any router.

I understand that it is possible to set up gateway at the nodes manually, or use SLAAC, or DHCPv6 and it should work in someway. But may be there is more beautiful native solution that allow setting priority of gateways and so on?