In a post in its Android Help Community, Google has stated that the owners of new Huawei devices should not sideload Google apps because doing so carries a high risk of installing altered software. Further, as the devices are uncertified by Google, the apps may not run reliably which could leave devices open to further issues.
As part of its unrelenting attack on Huawei, the U.S. government added the Chinese firm to its Entity List which prohibits U.S. companies, like Google, from collaborating with Huawei. These measures mean that Huawei devices released after May 16, 2019, do not come with Google apps such as Gmail, Maps, YouTube, the Play Store, and more.
Commenting on the matter, Tristan Ostrowski, Android & Play Legal Director, said:
“Due to government restrictions, Google’s apps and services are not available for preload or sideload on new Huawei devices. … In addition, sideloaded Google apps will not work reliably because we do not allow these services to run on uncertified devices where security may be compromised. Sideloading Google’s apps also carries a high risk of installing an app that has been altered or tampered with in ways that can compromise user security.”
If you find yourself in the unfortunate position of getting a phone without Google apps, there are third-parties that supply the packages. The Open GApps project is one of the places you can download Google apps. The project is a safe place to download the software from and is recommended by LineageOS, a popular custom ROM. Unfortunately, this method of acquiring the applications does require a bit of technical knowledge.
Source: Google