ARP Connector functions which is not supported in Dremio to source

we are trying to execute function which is there in mysql. but which is not supported in dremio function registry.

function which is not supported in dremio, but mentioned in ARP file and its supported at source, will it push down to to source?

We tried and its throws failure in parsing query.

Please help us on this. we are almost stuck due this for a while. Your response on this will be very much appreciated