Starting with v1.0.2 (currently waiting for review at the time of writing), yes it can. This allows you to combine Focus Filters with Smart Lists and create complex search filters with just a few clicks. Previously the Focus Filter was a global setting, and changing it affected all lists. This behavior has now changed in favor of greater ease and much gained productivity.
As an example, if you wanted to create a Smart List that would:
1. Show Starred Items
2. Items Overdue
3. As well as Items due within in the Next 3 Days
You would do the following:
1. Click on the search button to expand the search field and then from the search presets menu, select ’All Tasks’
2. Click on the [+] button to save this as a Smart List
3. Select the newly created Smart List and click on the Focus Filter drop-down. Now make the following selections:
4. Click on the little ’sun’ icon to switch Focus mode ON.
From now on, selecting this newly created Smart List will show you all tasks that are either Starred, Overdue or due in the next 3 days.