Here are more headcanons/ similarities of Ladynoir and Superbat because I'm way to invested in these ships.
1. Cat Noir and Batman both flirt with their superhero partner.
While Cat Noir as hero is generally more flirtatious and shows his affection towards Ladybug, Batman is secretive and behaves extremely professional.
Nonetheless both of them have some amazing pick-up lines they (sometimes) use at the worst time possible. And let me tell you, you can't compare these lines to cheesy stuff like 'Did it hurt when you fell from heaven?'. No, these guys are pros at flirting and know how to use words.
Ladybug is used to this and found a way to hide her excitement, so Cat Noir has to get creative. Batman on the other hand can easily turn indestructible superman into a blushing mess, what makes things so much more fun for him.
2. Clark and Marinette love watching their partner.
Sure, you can say it's the same with Bruce/ Adrien but I see some differences here.
Both Clark and Marinette do things that require a good eye for the little things. The things someone else might not pay attention to.
Clark naturally does ist with his superpowers, the job as journalist does the rest. With Marinette it's nearly the same, she just loves to create fashion instead.
So both of them directly see the habits their partner has. A furrowed brow, chewing on lips, playing with a pencil while thinking.
They love to watch Bruce/ Adrien without any ulterior motives (because let's be honest, that's what Bruce does. He observes and doesn't just look) and enjoy the time they spend together.
Every glance while their partner isn't looking makes their day.
3. They danced around each other for so long everyone went mad.
This should explain itself pretty good. I think both ships had a really long 'talking stage'.
After they revealed their identities and found out about the alterego of their crush things got awkward. It took some time to adjust and accept the fact partner and crush are the same, but they became an even better team afterwards.
After that it got clear pretty fast that feelings were involved (for everyone except Superbat and Ladynoir).
I think at this point eveyone knew that the pairs were head over heels for each other, wether it were Alya, Plagg and Chloé or Alfred, Lois or any of the batkids.
At first it was funny watching them dance around each other. All the tension, flirting and 'dates' that definetly weren't dates.
Then it got annoying. Time went by and nothing happend. No progress at all. How could they be so dense?
The fun was gone and all the superbat/ ladynoir interactions made their friends and family nearly explode. Even some help (from Dick or Alya) didn't work out.
When the ships finally sailed Lois was throwing a party, just as Alya.
4. Batman and Cat noir love the strength of their partner (not in a sexual way).
Superman is incredibly strong, I don't think i need to say much more. This guy can move planets if he wanted to.
Ladybug might not move planets, but let me tell you, this girl can carry buses, buildings, even the Eiffel tower.
With superbat it's easy to say that superman is physically stronger, with ladynoir it's a little different. I think they are nearly equally as powerful with Ladybug being a little stronger.
In the beginning this fact wasn't really that spectacular to Batman/ Cat Noir until their partner did something to show their power and they were simply at awe.
Were they fascinated? Impressed? In love?
Maybe (for sure) all of it. From that moment on they always watched Ladybug/ Superman secretly while fighting because them beeing so absurdly strong makes them feel things.
They may be jealous sometimes, but most of the time they just love their partner for beeing so strong and using it for the greater good.