Report transformations is a way to get country-specific functionality into Manager without hard-coding it.
What you require could be solved by custom reports or could be generic built-in features.
For example, duplicate transaction numbers shouldn’t be a report. That should be shown as an alert directly under the tab if there is a duplicate.
Transaction count by transaction type could be a custom report.
You are proposing quite a few bullet points, but there is a story behind each bullet point, isn’t there?
So each bullet point should be separate idea if justified by use-case and we can find the best way to implement this. And without resorting to custom coding.