No, it can't be used in the Huawei P30 Pro, that's an SD card, they don't fit. Unfortunately, Huawei has developed its own memory card for the P30 Pro smartphones that can only be used in Huawei devices. This card is called a nano-memory card, which in my eyes is quite a mess and not customer friendly. This card would be for the P30 Pro:

HP NM-100 (microSD, 256 GB, U3, UHS-III)

So you can already see from the high price that Huawei is quite a rip-off with the NM cards, because a 256 GB microSD card (which doesn't fit) would be available for 256 GB for about 30 francs.

No, much too big. Usually, microSD cards are used in smartphones. However, the Huawei P30 Pro uses something else, namely so-called NM cards (nano memory). However, this size has not become established and can hardly be bought anymore.

https://www.gsmarena.com/huawei_p30...
https://de.wikipedia.org/wiki...