Yes, you can have an
itemListElement property can take every Schema.org type as value. If the position inside the list is not important (i.e., the entries are not ranked), you don’t have to use
ListItem, you could use
WebSite directly instead.
To make sure that a consumer doesn’t mistakenly consider all the
WebSite items to be about the current website:
Note that Google Search provides a feature that makes use of
ListItem: Carousels. But this doesn’t apply to lists with
WebSite entries. So if you get errors/warnings in Google’s Structured Data Testing Tool, they might be related to this feature.