I don't really understand the question, but the resources suggested in How I can add my custom graph visualization in kibana
together with recent code (like current markdown or metric visualization) should help you get started.
things didn't change much since 6.0, but there were some minor changes, but you should be able to spot those from our current code. (maybe even compare metric code between versions ... however it was ported to react lately, so that might complicate stuff a bit)
in general we no longer recommend writing your visualizations in angular, as we are migrating away from it.