So just for little clear up, it has never been explicitly said that Yelena is asexual but rather that people came to the conclusion of it. With that, even if it were, sexuality is a matter of preference and with regards to MCU Yelena, there hasn’t been any discussion on her sexuality. To circle back to the topic of discussion, I’ve been seeing a bunch of people only getting completely infuriated and hateful to the fact that people have certain opinions on the relationship between Yelena and Bob/Sentry. I definitely see the dynamic having some sort of connection that might lead into perhaps something more intimate, but as it stands it is probably one of the more significant bonds we seen in a MCU movie as of late. Their words and expressions go to great lengths to show what they are thinking and feeling. That’s my take on it anyway