Subsite web part
Allow highlighted content web part to show subsites. Or create a site contents web part to show a list of subsites/libraries on the home page.
Would be extremely useful if it works. Shows only the site, not the subsites.
The key here is to get the scope to just the current site's subsites - at present the closest you can get to is all sites within a site collection (but this will include parent and sibling sites)
Andre Monaghan commented
These options would be extremely useful if added to Highlighted Content Web Part.
Source: This Site Collection
Source: This Site
Be really useful to have web part on the communication sites for all subsites. Especially when you have lots of projects rolling up into one PMO site.
Benoît Fournier commented
It would also be useful for the hub scope. List all the hub's sites I have access to.