We are working on upgrade project from AX2012 R3 to D365FO. The project is in starting phase and we are doing project evaluation and effort estimates.
Upgrade analyzer tool provide useful information for a smooth upgrade experience, as per document - https://docs.microsoft.com/en-us/dynamics365/fin-ops-core/dev-itpro/migration-upgrade/upgrade-overview-2012#run-the-upgrade-analyzer
But it looks like Microsoft has deprecated system diagnostic feature - Removed or deprecated platform features - Finance & Operations | Dynamics 365 | Microsoft Docs
Is there any alternate option of system diagnostic tool?