TL;DR: The problem isn't the shaders, it's something else.
It should! A shader mod does not actually do anything server-sided, so this means that the server can't see if you use this mod. This means that it does not influence your conection and the way you connect to servers.
However, the mods used to load the shader (Forge) can be spotted by the server (Because it is also useable in servers which use mods) in LAN as well as a "normal" server. This, however, should also not influence your connectivity because you installed the exact same mods and versions.
You will therefore see that if you uninstall the mods it should give you the same result.
Because these should be compatible, our question than really is: "Why can't I connect to my LAN server?"
There are a few things that can block your connection. Try tweaking your Pc's firewall of the Pc you're hosting on. That might be the result of a setting which does not allow some programs, including Minecraft, to pass trough your firewall.
This might be stupid to say: are your Pcs connected trough LAN? I figured they would but you can check it.
Check if your hosting Pc is using a lot of bandwith and try bumping it down, it might not have enough speed to get a reply in time.
Try uninstalling the mod server-sided when using the Minecraft_Server.exe
because the mods don't have to be installed there.
Try just opening a world to LAN instead of using Minecraft_server.exe
if you use that.
Note: minecraft says there is server maintenance but that might not be the case!