idk if this counts as “unlikely,” but these two def have the most underrated friendship in the series.
Like, riza is such a mom to the boys, but I feel like she would also be considered a motherly figure to Winry? She’s def someone Winry admires, and I feel like it given the chance they would probably become quite close.
Also, I lowkey headcanon that Riza knew Winry’s parents during the Ishvaal War–not personally, but they were really kind to her and made a huge impression on her. Their deaths probably hit her kinda hard, but seeing Winry grow up and have such a full heart comforts her :’)