Back on October 2018, Huawei launches its Mate 20 series smartphone by including a new generation expansion storage. Instead of microSD card, Huawei launches the NM Card. Now, we can see that Huawei might not be able to include microSD card slots into their devices. This means the only option Huawei has is the NM Card.
The main reason for this removal is the SD Association has removed Huawei from its list of members companies. The SD Association is established to set a standard for memory cards. This association is also responsible to promote newer SD card technologies. Since Huawei is officially out of this association, it won’t be able to produce any of their smartphones with SD card slot.

If you notice its other smartphones such as the Huawei P30 Pro, it is using the microSD card slot for expandable storage. Most of its affordable smartphones come with the microSD card slot. We are suspecting the whole reason the SD Association removes Huawei could possibly due to the ban on Huawei.
In conclusion, this will really affect Huawei’s affordable smartphone market. Huawei will either include its NM Card technology or its next-generation smartphone will only have the internal storage. As for now, Huawei has not provided its official statement regarding this removal.