After many months waiting Huawei release official tool for creating new watchfaces for Huawei Watch GT, Watch GT 2, Watch GT 2e and Watch GT 2 Pro. You can download it directly from Huawei official site.
First of all, download and install official Huawei Watch Face Designer. After first start swithc application to English as show picture below. Once you finish your first watchface, you can also upload it via Huawei Developer Console and if everything is fine, than your watchface will be soon available in official Huawei Health application.