It’s not possible because transactional data are in general combined into services. Service is something on top of All hosts that are serving them. What you need is taking timeries data from each service instance that is working on all processes that particular host serves https://www.dynatrace.com/support/help/extend-dynatrace/dynatrace-api/environment-api/metric-v2/sele...
In general you have to first list all processes on particular host, than check on each process what services are there (to get ID’s of them) and than try to check data from those hosts via timeseries API with filtering particular service instance.
here you have option to use parents transformation that should work for you. But as I said, you have to know ID’s of each process group instances that are working on particular hosts. When you will extract those data you have to calculate them manually to have them on host level.