Use MacOS Keyboard and Mouse or Trackpad to Send Texts to Android Phone Users 

Up front honesty: this is convoluted, but it's what the petty wall between the Windows & Apple ecosystems affords us at present. However, if you have already made the effort to use Barrier to control a MAC & Windows PC using a single keyboard & mouse/trackpad, then this additional benefit is just one step from where you are.
Admittedly, there's no way to use the Mac keyboard & mouse to send the text messages to Android users from within MacOS, but you can leverage your Barrier setup to do it through Windows. Let me show you how it's done.
For me, I do need to often send detailed text messages to Android users. It is convenient to be able to do so from my Mac keyboard and mouse. Please like & subscribe. I will absolutely do the same for you if you have your own channel.