If you are familiar with WordPress, it always helps. Moreover, in WordPress, Yoast SEO has many options for writing, including readability score, active voice indicator, subheading distributions, etc.
Companies look for content writers who can directly publish content without any onboarding to WordPress and Yoast SEO.
If you are not sure about WordPress and Yoast SEO, I will recommend you to start a blog and get used to them. As a content writer, it is a critical step.
Moreover, Grammarly is A Must-Have Tool for Every Writer.