Well, I really don't know, but AFAIK the title name is not stored in .brlyt files (these are responsible for the actual banner layout and graphics).
In disc-based games, these names are stored at the beginning of the opening.bnr file, the "IMET header". I don't know if the BRLYT tool can modify the IMET header, but if it does, you should be able to use that to copy the japanese name to the other languages' slots. If the tool can't handle the IMET header, edit it with a hex-editor, but be sure to read up on the format or check a file from your region before you attempt that. There might be differences between the NTSC/J and PAL IMET header I do not understand, but I have found no such differences.