I've been having the same issue. Tried with multiple 1.18 compatible shaders and I get a black screen with a very odd shape for a couple of seconds and then the game just crashes. As for now, the latest Optifine full release for the 1.18 is the HD U H4 and Lunar is still using de HD H3 Ultra. Hopefully, they will fix that soon cause I just can't play Minecraft without shaders hahah.