If you don't publish regularly, you're not ready for social media.
You are excited about your agency or product launch. Blog posts are essential to the health and findability of your website. I know you don't have time to do it. That's why I'm here to help you.
Your WordPress product is awesome; if you don't have blog posts, what will you share on social media? Your WordPress agency just launched a website for your client. How will anyone know?
Fortunately, this is a problem that is easily solved with short-form content. Publishing as regularly as possible is best.
Document your work with case studies and reviews on your own website. Don't rely upon Facebook or Twitter. Don't rely upon a link to a website that may get changed later.
Instead of talking about the features of your WordPress plugin, educate your audience on why they need it. Why do we need your service?
If for no other reason than this: is your product or service still available? Or are you just another abandoned product in Open Source?