The footwear giant posted another apology -- their second in the last few days -- early Sunday morning ... acknowledging connections are still being made between the Munich Massacre of the 1972 Olympics and their recent SL72 campaign.

Adidas says the connections weren't meant, and they apologize -- all falling right in line with the apology they issued earlier this week after the American Jewish Community called them out.

This time they specifically apologized to their partners too ... saying sorry in their statement to Hadid, A$AP Nast, Jules Koundé and others for the impact this may have had on them and their careers.

Apologizing to their models marks a huge step for Adidas ... and, one that can be seen as doing some damage control -- 'cause we know at least one of them's considering legal remedies.

We broke the story ... sources familiar with the situation tell us Bella Hadid has retained legal counsel to take on the clothing company -- blasting them for a lack of public accountability and for spearheading a cruel and damaging campaign

One of her main gripes, we're told, is that Adidas would put out a campaign that would associate anyone with the tragedy in '72 where 11 Israeli athletes were taken hostage and executed.

And, looking at Adidas' statement, it seems like they're trying to apologize to all of the points these sources raised ... so certainly possible they're trying to avoid a legal issue.