Thank you for reaching out to us again!
The law that you are talking about, that we had a look at in a previous thread, is supposed to come into effect on 01.01.2020.
Unfortunately, that means I can't tell you (yet) how the application process will look like and what documents are necessary in order to receive said "Beschäftigungsduldung". The same applies to the language level you need - sources I found only speak of "sufficient German language skills".
If you fulfill the requirements that I listed here and have no criminal record, you may be eligible to apply in the future.
For now, that's all I can share with you, but I'll make an update once I hear/ read something new.
All the best,