Moving Photos to iCloud.

My wife has an extensive Photo Library consisting of almost 200,000 (2.38tb) images in various formats (jpeg, png, psd).

Of the library there are currently 50K in Apple iCloud.

We purchased 6 additional TB from Apple to keep everything working seamlessly between devices.

We have 98K on an external HD that we are trying to upload to the iCloud and I have tried using Photos, Option, System Library, file, Import, chose the 98K, start the upload and it fails overtime.

Would anyone here have options that I might use to complete this process.

Thank you.