Separate WAN and LAN throttling

I'm running 23.05.05 r2410OpenWrt 23.05.5 r24106-10cc5fcd00 / LuCI openwrt-23.05 branch git-24.264.56413-c7a35626 and tried using qos over nftables to throttle internet download speed on a couple devices and that seems to work. However, I don't want to limit the LAN bandwidth.

I am limiting Roku download speed (getting lower TV resolution) in order to not overload my poor internet service. However, I have a local media server that serves up local content to the Roku ... but it is throttled as well, and the local content needs greater bandwidth than I have configured these devices for.

It seems like there should be a way to limited non-LAN bandwidth usage and have a different (or unrestricted) LAN bandwidth limit.

I am running an OpenWRT router the Rokus are connected to via wifi. It is joined to the lan by wifi link to the router (also running OpenWRT) that then uplinks to the internet.

Any suggestions?

Brian