Hello @xyz,
Unfortunately, it is not possible to select a Static Block in a Sub Menu item directly. If you wish to use a Static Block in a Sub Menu item, you must create a new Custom Sidebar in Appearance >> Widgets. After creating the Custom Sidebar, add the Static Block widget to it and select the Static Block. You can then choose the sidebar in the Sub Menu item by editing it in the Widget area. We have created a video to demonstrate this process, which can be viewed here: https://www.veed.io/view/25819cbf-7b99-4790-95ae-f230428b163d?sharingWidget=true&panel=share
This is the only possible way.
We hope this information is helpful.
Best Regards,
8Theme’s Team