IMHO, these AI plugins at least in the current state are more experimental. Use them at your own risk. I have not tried AssistAI, but I know for example Copilot4Eclipse even can damage an existing Eclipse installation, causing standard functions to break. You will need a new fresh installation of the Eclipse distribution.
This potentially might get more mature over time, but that might take time, depending on the quality of such AI plugins.
As you already mention VS Code: NXP supports it and provides extensions for it, so if you really want to use AI tools, then you have a choice.
I hope this helps,
Erich