Sorry for the late reply. Yes you can do that.
You can create a shortcode called “disclaimer” with your needed content.
Then at the top of every post you can manually insert the shortcode like
You can find more docs and examples here – https://www.aakashweb.com/docs/shortcoder/custom-parameters/
In case you want to do this for every post automatically without shortcode then you may need to check with your theme dev to insert custom text after the title.