LineageOS 14.1 latest update (not sure how far back works) will allow me to select removable storage or adoptable storage when it first detects an SD card.
Not only that, but I started out with 14.8GB internal storage instead of the 10GB that the stock ROM shows from Huawei. That's an extra 4.8GB. Additionally, the system doesn't take up as much, so I actually had over 11GB free before I started installing my apps. I've got 132 apps installed to internal storage, and still have over 4GB available.
This version does not allow me to install apps to SD card without using adoptable storage or using "other" means, but with the extra room, it's not necessary for me. Internal storage is also faster, so I'm happier being able to put it there.