AWS Batch analog in GCP?

I recommend checking out dsub. It's an open-source tool initially developed by the Google Genomics teams for doing batch processing on Google Cloud.

You can do this using AI Platform Jobs which is now able to run arbitrary docker images:

gcloud ai-platform jobs submit training $JOB_NAME \
       --scale-tier BASIC \ 
       --region $REGION \ 
       --master-image-uri gcr.io/$PROJECT_ID/some-image

You can define the master instance type and even additional worker instances if desired. They should consider creating a sibling product without the AI buzzword so people can find this functionality easier.