Vuforia alternatives

Tldr: I need an easy image recognition plugin for unity with a free or cheap license ideally it needs to work for IOS and android.

I'm developing a treasure hunt app in unity for a company that handles exchange students, the idea of the app is for the kids to discover and explore the city. The way I have designed the game is the players receive instructions on where to find an object and they need to scan the object to receive the directions for the next clue, so there's no fancy stuff going on I only need Vuforia to detect objects. Some of the following objects are stuff I want to detect although there is some leeway:

 

!bump

 

ARFoundation? it's free and has image targets. Also possible other features that might be usefull for you app.