Exemplars? OpenMetrics?

Apologies in advance but I have a rather rudimentary understanding of this topic at the moment.

My goal is to get Istio metrics to be scraped with exemplars so that I can link metrics with logs and traces using trace ids with Prometheus, Tempo and Loki. I have some of this working by exporting traces via zipkin to Tempo and grabbing the trace_id from logs using Loki, but I’m not getting any exemplars in Prometheus from Istio metrics.

My understanding is that exemplars are currently only created when exposing Prometheus metric endpoints in the OpenMetrics format. I’ve searched around and outside of some DataDog stuff that doesn’t really line up with what I’m expecting I’m not finding a lot of information. Is this currently possible and if so does anyone have any advice on how I could find more information on setting this up?