So basically I can't use Lightroom on iPad the same way I use Lightroom Classic? Just import files from SD card from camera and edit them locally, and when finished photo shoot editing and exported it and sent to my customer, then move it to NAS server. Is there any possible way to change storing something in cloud to just copy / move it physically between device and external drive?
Since Adobe Photoshop is coming to iPad Pro, can't we also have Lightroom Classic? I do understand Cloud Based app but I don't won't to work on photos in cloud - I prefer to have them locally and backup myself on external drive.
You certainly can import files from the SD card, so on my iPhone8 I use the SD card to Lightning adapter and edit them on the phone. These original photos are automatically downloaded to your computer and your Lightroom Classic catalogue where there is a preference to set the download folder, which can be your NAS. The preference is on the Lightroom Sync tab.
This automatic process is via the cloud, not via LAN or physical connection. So from Lightroom iOS the originals are uploaded to Adobe's server and then down to your computer. The app has an option to limit this uploading to when you have a wifi connection, so you don't use mobile data. Once you see the photos in LrClassic, the originals are physically on your system and you can safely remove them from the cloud - eg remove them from All Synced Photos in the Catalog panel - and this helps if you have a 20gb limit.
If you still want these pictures to be available on your iPad, you can sync them again from LrClassic but they now sync up to the cloud as smart previews and don't count against your storage limit.
I am like you as I want to keep my originals on my own system, so last week I imported a morning's raw files into my iPhone, which has no data plan. Over lunch I had a wifi connection, so some of the files will have uploaded to the cloud, and I made a few rough edits and sent someone a picture. On the way home I had no connection but still edited a few others. At home the phone connected and later that evening I went to my main PC and could see that all 130 had arrived in my folder system. I then unsynced the collection, which is another way to remove originals from the cloud, and synced it again so that I would be able to access the smart previews if I wanted.
So while it's not LrClassic on the mobile device, it's still an integrated workflow that allows me to store originals where I want.