Dear @Serhii V,
I am not aware of any specific rules for Ukrainians coming to Germany from other non-EU countries where they have already received a humanitarian residence status.I have searched but also have not found any specific information on this.
In the case of Ukrainians moving to/from Germany from EU countries, the rules are clear.
The central requirement to receive a 'temporary protection' residence permit in Germany (also referred to as paragraph 24) is that the individual was resident in Ukraine before February 24th 2022. You will need to have proof of this to qualify.