QB Issue Resolution:
You cannot with QuickBooks Pro. In order to do this en masse you need the accountant’s version. The only option with Pro is to edit transactions one at a time
Resolution for Issue 'how to change classes for multiple transactions all at once?' available: Yes (Solved).
Source: Intuit Community forum.
how to change classes for multiple transactions all at once?: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.Support for change classes
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Error Recovery for change classes [Canada]
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