Hi, Asaf.
I would guess that what you request would be difficult-to-impossible using standard Android share. For a text-based share the originating app sends title and text and I don't believe that there is any other parameter suitable for sending folder. MLO could set up a special share to receive title, text, and folder but it only be accessible from apps programmed to send title text and folder, of which there are probably none. Also, once you open this door you are very likely to hear from other users wanting to share start date, importance, context, due date, and even the less-frequently-used ones like isfolder, isproject, ischildof, effort, etc etc.
Fortunately, MLO contains a structure for coding all of this, for example if you wanted to create a task to review accounts receivable, two weeks from today, and store it in the folder "work" you could specify
Review A/R -s 2w -tofld work
Where the -tofld operator stands for "to folder"
To use this you would need a way to tell MLO to parse the text you are passing.
You are asking for a specific interface to allow a task created by Android share to specify a destination folder but I suspect that a way to request parsing of text passed through Android share would resolve your issue and would be easier to understand, code, and market.
-dwight