Is there any plugin that can....?

Is there any plugin/package that can internally route connected client devices through a proxy of my specification on the host network?
I have to use a proxy to get online through my phone.
I bought an Archer C50 v5 to use OpenWRT on.
I got it in the hopes that there'd be an OpenWRT package to do the proxy connection for the connected client devices.
That way said client devices don't have to connect to the intranet proxy on their end.
A lot of stuff on my client devices doesn't play that well with proxies.
The proxy is intranet only.
Meaning the sites and services connected to will still see the same thing as before setting up a plugin for this.

would that be enought ?
wouldn't you need to "convert" the traffic from regular to routered through the proxy, without the clients being aware of it ?

over vpn is a good option too

I think your best bet is running squid running as a transparent proxy and connecting through a parent proxy.