If the focus is on a blessing which comes from the LORD, what is done in creation should serve as a starting point on which to build understanding:
And G-d blessed them, saying: 'Be fruitful, and multiply, and fill the waters in the seas, and let fowl multiply in the earth'. (Genesis 1:22 JPS)
It is possible G-d was kneeling but the ones receiving the blessing were not. Also, since the first blessing was given to living creatures, the expectation is that all living things would be blessed. That is not what happens:
And G-d blessed them; and G-d said unto them: 'Be fruitful, and multiply, and replenish the earth, and subdue it; and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that creepeth upon the earth'. (Genesis 1:28 JPS)
Other than man, everything created to live on the land (including all plant life created on the third day) was not blessed. In terms of kneeling there is no conclusion either for or against.
The final blessing during creation was the seventh day:
And G-d blessed the seventh day, and hallowed it; because that in it He rested from all His work which G-d in creating had made. (Genesis 2:3 JPS)
The day was not kneeling, perhaps G-d was. It is interesting that the seventh day was blessed but days 1 through 6 were not. The reason for giving this blessing was "He rested from all His work." Yet the first two blessings came as a result of (and during) His work. Since the command to observe the Sabbath is going to come from the events of the seventh day, unless kneeling is part of G-d's blessing, it would seem to be less important than what the actual blessing was.
If the question about kneeling is expanded to consider whether the one receiving the blessing is kneeling, the question on the blessing from the sixth day would be: Did G-d kneel when He blessed the man and woman, or did they kneel when He blessed them?
Kneeling before someone is normally seen as a gesture of honor and humility. A person would kneel before someone to demonstrate respect or honor to the other; a person kneels before someone to humble themselves to the other.
So would man humble himself before the LORD G-d? Or would the LORD G-d humble Himself before man? I think the answer to that question is the point of the rest of the Bible.