From wiki:
QuoteLibreELEC 10.x also dropped support for Raspberry Pi Zero and other 512MB RAM devices as 1GB is now considered as the minimum RAM needed for a good Kodi experience.
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Pi3A has 512M and is not supported. Pi3B has 1GB and is supported.
You could try LE 9.2.8 which may be somewhat usable (as long as you don't want the latest add-ons to work).