wooden desk with iMac and magic mouse and keyboard has color samples and other design tools scattered about, an image of a toolkit laptop and smartphone is on the screen

Yes, You Need a Style Guide

What is a style guide? A style guide is a document that outlines how your organization should look or be credited in print, web, or other media. I can't tell you what to do, but if I COULD I'd tell you to invest a few dollars or a couple of hours to clarify your organization's voice.