You can use get_rate
to convert your counters in 1/s
Here is a very basic excample:
from time import time
from cmk.base.plugins.agent_based.agent_based_api.v1 import (
get_rate,
get_value_store,
)
now_time = time()
value_store = get_value_store()
value = get_rate(value_store, f'your_name_for_the_counter_in_value_store', now_time, your_counter, raise_overflow=True)
yield Metric(name=f'your_metric_name', value=value)