I think that this comment goes here because it's about the crossover as a whole, and not the individual episodes.
The crossover really didn't work for me at all for several reasons.
First, I thought that the characterisation was non-sensical. I mostly noticed it with Arrow because that's the only show I watched, but I still don't think it's fair to any of the characters to effectively boil them down to a few personality traits that don't actually match their history. I thought it would have been a lot better if rather than saying that Oliver uses his 'darkness' and Barry uses his 'lightness' to actually do the opposite. Show that Oliver finding a family has made him a happier person, and that fighting for them makes him better. Show that Barry has had a tough time, and that he uses those experiences to become a better person. It would have been much more interesting for the characters, and this particular viewer, to make them confront the ideas and prejudices they've had about eachother rather than imply that those prejudices are correct even after years.
I think that if you're going to keep the side characters on seperate shows, it would have been much more fun to lean into that more. We saw how Oliver reacted to Team Flash, and it would have been really fun to see how Barry reacts to Oliver's life. There was slight tinges, but things like him wondering about how the team works now that they're based at Argus and being utterly confused about the changes would have been fun. And also being easily recognised as former Mayor etc. Basically, since this is a smaller crossover than last years, they could have made the most out of it by showing the differences and similarities on both sides.
It was also a blatant set up for Batwomen. I expected this, but I didn't expect them to go about it so badly. It was unfair to add this to an already bloated cross over. It made for really boring scenes since RR seems to have little charisma. It was mainly full of Easter Eggs that, as a non-comic reader and someone who isn't particularly interested in Batlore, just flew over my head. It reminded me of the previous cross over starring 'The Hawks' and Vandal Savage which was just used to set up LOT, and reminded me of just how bad it was. There's a reason I never watched LOT, that episode and a strong dislike of Ray Palmer. This episode is the reason I will not watch Batwoman (should it ever reach the air).
Finally, as predicted, it was a dickfest. Even on her own show, Supergirl barely had anything to do. Last year was really fun because we had pairings like Iris/Felicity. We got to see how they'd work work together, and whilst I understand why we couldn't get that this year, I don't get why we couldn't see Kara work with the others on their individual shows.
The whole cross over could have been much more tightly written. Instead it was bloated with the addition of Batwomen and fell on old stereotypes that don't even apply to the shows and characters any more. It had to be smaller than last years cross over, but they simultaneously tried to make it more 'epic' and that didn't work. They should have used the fact that it's a smaller cross over to show the more day to day aspects of Barry, Oliver and Kara. They could have shown how the shows have changed since that first cross over, but instead I'm left feeling like Barry is exactly the same as season 1 Barry, who is the reason I stopped watching the Flash. I doubt that that can be true 5 seasons later, but they squandered the opportunity to show me, and other people who gave up on one of their shows or who never started watching, just what has changed.