The system is only one part
Cross-border complexity often sits between local requirements, group processes, master data, vendors and professional interpretation.
Standardise the core
Use common process principles, data definitions, controls and reporting while documenting justified local variations.
Make validation explicit
VAT status, company identifiers, transaction type and evidence requirements should be visible control points rather than informal knowledge.
Connect local and central teams
A clear operating model defines who owns decisions, who maintains data and how exceptions are escalated across countries.