A lot of "standard" US Keyboards get creative on placement of the "pipe" (aka the "|") I imagine it is the same for a lot of languages, just not as bad from the lower number of computer sellers for other languages.
For example, if you consider a keyboard to have 5 rows (with the bottom being the CTRL, ALT, spacebar, and menu keys), I've seen different layouts over the years with the pipe key being in any of the top 4 rows, and not always as the "shift" version of "\". The most common location is directly above the "enter" key, but I've seen keyboards with that location being an extension of a much larger "enter" key that crosses 2 rows. On the "large Enter" types, they will often have the "\ |" to the left of the "Enter" key (on either row), above it (with the "Backspace" key, normally double-width, reduced to single width, and the Pipe/Backslash taking the spot its left half would be), or below it.
That's not even getting into the minefields that are laptops and "alternative layout" keypads - let alone other languages.
Typically, if you want easy access to backslash or the pipe, you want a keyboard set up for programmers, as I believe the pipe is used in some programming languages.
My suggestion, if you have a non-English keyboard where finding the keys for some of the chat commands are difficult, look on your keyboard for symbols you NEVER use in chat, and set them up as macros for the hard-to-access ones.