Choosing Portable Functions for Spreadsheets Shared Between Excel and Google Sheets — Replacing XLOOKUP with SUMIF for Compatibility

When you author spreadsheets locally in Excel but share them via Google Sheets, function compatibility becomes a real operational bottleneck. This post covers a case where XLOOKUP broke on Google Sheets import, and the SUMIF / INDEX+MATCH replacements plus reconciliation cells that make sheets survive the round trip.