Crashpad's sanitization logic is only fully hooked up on Android, but shouldn't be too much work to hook it up for other platforms.
At a high level, the client process (your application) creates a
SanitzationInformation struct describing the sanitzation configuration and communicates the address of the struct to the crashpad handler process. When a crash happens, the handler reads the struct from your client process and sanitizes the dump accordingly.
On Android, the struct address is communicated either in a message the client sends to the handler when it requests a dump or on the command line to crashpad_handler, but this is only because of particular requirements for Android and WebView.
To plumb this out for other platforms, I'd suggest adding a
CrashpadInfo::set_sanitzation_info_address() and make sure to update the
CrashpadInfoReader. Then, for Linux, you should be able to
get the address from a CrashpadInfoClientOptions here and use it to configure sanitization just below that. Other platforms have similar code under hander/<platform>/crash_report_exception_handler.cc but need a little more of the logic that's already there for Linux.