Hi Zoo,
I think this largely depends on grafana's capabilities to pull data in. Unfortunately, myself being more familiar with OCI, I cannot attest to those capabilities.
In any case, OCI comes with an open REST API and you can get data out of OCI with anything that can issue REST calls.
Of course, that might not be strictly necessary in this case, since you definitly can export performance data from OCI directly into a csv file. Ok, from the web-ui it can be a bit tricky, but the reporting portal is particularly well suited for that.