Hi Morticia.
Find template for stock picking import below:
Operation Type/Database ID | Contact/Database ID | Source Location/Database ID | Destination Location/Database ID | Stock Moves/Description | Stock Moves/Demand | Stock Moves/Product | Stock Moves/Unit Price | Stock Moves/Source Location/Database ID | Stock Moves/Destination Location/Database ID | Stock Moves/UoM |
1.00 | 7.00 | 4.00 | 8.00 | placeholder | 11.00 | 2.00 | 10.00 | 4.00 | 8.00 | Units |
| | | | placeholder | 22.00 | 3.00 | 15.00 | 4.00 | 8.00 | Units |
| | | | placeholder | 33.00 | 4.00 | 20.00 | 4.00 | 8.00 | Units |
2.00 | 7.00 | 8.00 | 5.00 | placeholder | 2.00 | 2.00 | 10.00 | 8.00 | 5.00 | Units |
| | | | placeholder | 2.00 | 3.00 | 15.00 | 8.00 | 5.00 | Units |
| | | | placeholder | 2.00 | 4.00 | 20.00 | 8.00 | 5.00 | Units |
| | | | placeholder | 2.00 | 3.00 | 20 | 8.00 | 5.00 | Units |
| | | | placeholder | 2.00 | 4.00 | 20 | 8.00 | 5.00 | Units |
Pay attention, first 4 columns represent stock.picking and other columns are their stock.moves.
Actually, you can put any identifier instead of Database IDs, this is only my habit.
Pay attention that you must put partner_id (Contact) for outgoing and incoming pickings AND you always must put Stock Moves/Description in stock moves (it's mandatory)
Also pay attention to the Stock Moves/Unit Price field if you maintain automated costing method (FIFO or AVCO)
So
- Replace my ids of the operation types, locations, product variant and contact.
- Go to the Inventory - Operations - Transfers, and import your file in this stock.picking model

- As a result, you will have the classic transfers in the system



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I hope it is not a big issue for you to match the necessary identifiers; if it is, I suggest creating another issue.
I don't understand why importing sales orders is causing you so much difficulty, especially when odoo supports excellent Excel file importing. Furthermore, modifying an import template is not too difficult, and you can also create orders from any platform through the API.