Ok. let's see how it really works.
Your Report data
| Company | Item | Partner | Subas1 | Subas2 | Subas3 | Sum |
|---|---|---|---|---|---|---|
| 01 | 11 | 02 | 1 | 2 | 0 | 100 |
| 02 | 22 | 01 | 0 | 1 | 2 | -90 |
The system finds the amount of pair of CU. Summ their amounts: 100 - 90.
Storno all amounts, for both CU
| 01 | 11 | 02 | 1 | 2 | 0 | -100 |
| 02 | 22 | 01 | 0 | 1 | 2 | 90 |
And the difference 10 place to the CU with the bigger amount:
| Company | Item | Partner | Subas1 | Subas2 | Subas3 | Sum |
|---|---|---|---|---|---|---|
| 01 | 11 | 02 | 1 | 2 | 0 | 10 |
As a result, we eliminated the common liability (or whatever) 90 and -90. And left 10 on the Company 1.
And you said 10 is immaterial.
SAP often don't do exaclty entries the client wants. You need to convince them in it. The main things - the result is correct. And it doesn't require any reclasses or BAdIs.