To insert files in a Sheet in alphabetical order, do the following:
1. Upload the files in a Google Drive folder.
2. Use the FileDrop’s Drive tab, select the folder where you uploaded the files and sort files by name a-z.
3. On the keyboard click the Shift button and hold, and then use the left mouse button and click to select each file you want to insert, or click and hold Shift + the last file in the folder.
4. Click the top right Insert button and the files will be added to your Sheet in alphabetical order.
Please look at the video for details: