Detailed statistics can also be sent directly to an InfluxDB instance:
k6 run --out influxdb=http://localhost:8086/k6 script.js
The above will make k6 connect to an InfluxDB instance listening to port 8086 on localhost, and insert all test results data into a database named "k6" (which will be created if it doesn't exist).
Then you can use some other tool like Grafana to visualize the data.
Read more in this Tutorial about using k6 with InfluxDB and Grafana.