Are there any websites like simbrief I can use to plan flights to airports like zwak/zurk?
They do have charts and procedures in a so called “NAIP”, with only Chinese language on those. But unfortunately they are not legally distributable under some regulations so I’m afraid no one here should share or request them publicly for compliance reasons, you have to get them by your own
If you have those NAIP data available, you can use PFPX to plan those flights I believe.