Yes. You can set Fargate CE’s to have a max vCPU, which is the total amount of vCPU of all the jobs currently running in that CE. When your vCPU count hits max vCPU in a CE, Batch will begin scheduling jobs on the next Fargate CE in order attached to the queue, if there is one. This is useful if, for example, you want to set a Fargate CE to some minimum business requirement, then run the rest of your workload on Fargate Spot.
While setting a Fargate Spot CE as first, followed by a Fargate CE, Batch will only spill over into Fargate when the vCPU used by your jobs is greater than max vCPU for that CE. In the event that Fargate Spot is reclaimed, max vCPU will not be met and Batch will not request Fargate resources in the subsequent CE to run your jobs.
Connecting an AWS Batch job queue to Fargate/Fargate Spot CE and an EC2 or Spot CE is not allowed.