Check if your client is at least a 2018 one (iirc forcerendereffect.lub does not exist prior to 2018 clients although I'm not too sure about it)
Open the server's grf or data.grf. The lub file should be under \data\luafiles514\lua files\effecttool\forcerendereffect.lub
You can edit out/in ANY effect when you go /effect off in game, there's also instruction written on the forcerendereffect.lub, once you delete the effects you don't want to see, the client will only render the ones you include in the forcerendereffect.lub (under /effect off).

If your client doesn't have a forcerendereffect.lub file then ;(((