I currrently use the following plug-ins:

• Batcher
• Resynthesizer
• G’MIC
• Contact Sheet
• Frequency Separation Group
• Layer Group
• Offline Background Remover

I used to use one called BIMP for batch editing, but it doesn’t work since the update to 3.0.

I did see alternative called Batcher, but I haven’t had the chance to try it yet.