I have been a long time Transformers fan, this was both really funny and slightly cringey for me. During the episode several questions were asked so I have a few answers listed below. Sorry if it sounds like one of those "well, actually" comments, I just put this out in case if any of you are actually interested.
-There is not really a set amount of generations. G1 was just a fan term to differentiate it from the reboot G2. After this, no other generations were numbered and it is argued on what is even a generation.
-A person could fit in Cosmos, though he is pretty small, being only 4 meters in height. In later years he becomes much much larger, this is because having a solider that looks overweight is not practical, so his width is decreased in exchange for a increase in his height. Cosmos has the Autobot symbol on. Cosmos also turns into a UFO because he is almost only used for reconnaissances, he can go several times faster than light in this mode. Unfortunately this role makes him depressed because he can't be with anyone. To not be bored he uses his alt mode to scare humans into thinking that an alien will probe them, meaning that most flying saucer sighting in Transformers are actually just Cosmos being bored.
-The first photo that they use of Arcee is from Transformers Prime, she is blue because Transformers are sold primarily to boys, and kids usually don't like pink. Her head is indeed based off of Princess Leia. She was the first female Transformer to be designed, though their are well over a hundred at this point. 6 of them even made it on TV before her since the movie took longer to make.
-Kup is the stereotypical drill sergeant of the series, the picture that makes him look like a jester is when he is telling a war story. The reason his alt mode is so weird is because he still used his Cybertronian vehicle mode. In some series he does take an Earth vehicle mode which is usually a really old pickup. The picture that has Kup using a cigar is official. In the comics he had severe PTSD and his body was dying, he had many things done to him, but one was getting a medicine that made him forget when he went insane and murdered a bunch of his fellow Autobots because of the PTSD. When a human asked about the cigar, he did not even understand what a cigar was, so it just happens to look like a cigar. Transformers do not have lungs, you are correct.
-Ratbat was a Senator on Cybertron, he sponsored rebellions so that he could make a profit, one of his agents, being Soundwave, turned on him and took him prisoner. One thing about Ratbat was that he was racist towards animal like Transformers, (he was originally humanoid.) Because the Decepticons had no tolerance for racism, (their are actually more Autobots who are racist towards there own kind than Decepticons) they turned Ratbat into on of Soundwaves soldiers, that is why he is a cassette and bat. Over the course of a few million years he eventually became the leader of a faction of Decepticons, and many consider him to be one of the smartest leaders the Decepticons ever had. I am combining two continuities of G1 here, but this is just to keep things simple. Ratbat does have a new form but it is Cybertronian, this is so that Hasbro does not need to give him a new alt mode every decade.
-Hope this covers everything for now.