Last week, the Taiwanese government announced that ZTE would have to take permission before embarking on any business partnerships with a Taiwanese company. That permission has been granted now, though, allow ZTE to do business with MediaTek.
https://www.notebookcheck.net/MediaTek-given-go-ahead-by-Taiwan-government-to-trade-with-ZTE-as-latter-files-for-suspension-of-US-trade-ban.302868.0.html