Which Export Mode to use in Data Exchange Integration to override the data intersection?

Summary:

We have a data file where there are duplicate intersections. On prem Rule file is set to overwrite, so it loads the last intersection. But on cloud, when we run the integration with "Replace" as Export Mode, it is adding the values and loading to the specific intersections.

Content (please ensure you mask any confidential information):

Example:

Account→Entity→CostCenter = 100
Account→Entity→CostCenter = 50

On prem would load 50 as the rule file is set to override by on cloud it is summing up and showing 150 when loaded in "replace" or "merge" mode.

Is there any specific setting that needs to be tuned on ?