That's not something readily supported for a few years now. What you need to do instead is to format the card via your phone to have it used as internal storage. Then the phone will install apps between the actual internal storage and SD card as it sees fit. Beware this method means you should not take the SD card out at all, as it will mess up nearly all your apps, given app files are spread out.
Go to Settings, Storage, Micro SD, 3 dots for settings, format SD card as internal storage. Do be sure to back everything up currentl on the card such as music and photos first. The faster the card the better as well. I'd use a samsung evo plus UHS-1 card. I'd use at least a class 10 for this purpose, if yours currently is not.
To add: If you selected Portable Storage after inserting the SD card; system apps, user downloaded apps and associated app data cannot be moved to the SD card. Only pictures and media (e.g. videos & music) can be stored on the card.
If selecting Internal Storage and your SD card is too slow, your device will warn you during the adoption process. You’ll still be able to complete the adoption process, however app and data transfers will take longer to complete. The only downside to selecting internal storage is that the ability to move apps to the SD card is dependent on whether or not the app developer included this feature in their app.