If I license my article, will it decrease its ranking on Google Search?
It should have no affect to your site's ranking.
Once you license your article, the Written.com plug-in will notify search engines that your article has been moved to the brand’s site. Search engines will change their index and point readers to the brand’s site whenever a user accesses your content during the term of the license. During this process, search engines typically take three weeks to normalize the ranking of the content in its new placement.
Note that you would only redirect your article(s) to the brand for the term of the agreement, and you will be paid each month. At end of the term, the Written.com platform will redirect the article back to you.
In many cases, our brands have more highly authoritative sites, so when the content lives on the buyer’s site it actually becomes more valuable. When the content returns back to your site, the added value can transfer with the article, and in many cases, could potentially benefit the overall authority of your site over time.