In Salesforce Lightning Dashboards, chart legend ordering is not guaranteed when the grouping field is a picklist or formula field. The following scenarios illustrate common manifestations of this behavior."
This is an expected behavior as Salesforce doesn't guarantee sort order in the chart legend. Lightning Dashboards are not designed to respect field type ordering like picklists and formula. The behavior varies in different languages when these fields are translated. This behavior occurs because Lightning Dashboards do not enforce picklist metadata ordering when rendering chart legends. The rendering engine sorts legend values at display time based on data, not field configuration.
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