When comparing Avant Window Navigator vs Krunner, the Slant community recommends Krunner for most people. In the question“What are the best app launchers for UNIX-like systems?” Krunner is ranked 8th while Avant Window Navigator is ranked 27th. The most important reason people chose Krunner is:
Just by typing name of file or folder, it will give recommendations
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Tons of plugins
AWN comes with a big selections of applets such as a CPU monitor or clock or trash bin. This means one can easily turn the docks functionality into that of a taskbar. There is even an app launcher applet that will group all of ones apps in one place just like a start menu.
Pro Easily customized
There is a wide array of setting available to theming and customizing the dock.
Pro Opens folders/files also
Just by typing name of file or folder, it will give recommendations

Pro Extensible with plugins
Krunner can be extended with the use of "runners" which are essentially plugins for the app launcher to allow for extra functions.

Pro Fast
As it is written in Qt QtQuick using QML.
Pro Lots of handy features
Such as a fully featured calculator, file opening, browser functions, currency conversion, date/time functions, etc.
Pro Great integration with Plasma, developed by KDE
Pro Can be used to open websites
By just typing an URL into the text box users can have the site open in their default launcher.
Pro I'm able to find open tabs from browsers with KRunner which is very nice
Even supports edge browser.
Cons
Con Project is dead
Has not been update since 2013 and has been already pulled from many repos. While it still can be installed and works as it did in 2013, no more fixes or features are expected.
Con There are few plugins/"runners", and some do not work as they are old
