I’m confused by what you’re trying to do and why.
If you’re in Premiere you’re already editing.
Generally I’d recommend either using the camera native codec if the NLE and Mac can handle it. Otherwise encode to Apple ProRes. Depending on the source and goal that might range from ProRes LT to ProRes XQ.
Perian is legacy since it’s based on Quicktime Frameworks which is deprecated. Apple now uses AVFoundation. Perian will handle playback of some odd codecs but that generally wouldn’t help an NLE as modern Mac NLEs are using AVFoundation.
If you want detailed help you may want to read the sticky at the top of this forum and explain in detailed including software version and objectives. The more detail the faster and more accurate response you’ll get.