WMG / Men in Black: The Series

The Men in Black have knowledge of about half the other Sony-created movies/cartoons and their characters, creatures and equipment.

The MIB (in the cartoon-verse) keep tabs on the Ghostbusters, provided covert assistance to HEAT and Zilla when they fought against the psychic aliens, they've dealt with N-Tek (though after N-Tek's government funding was cut off, they have doubts as to how long Max Steel can keep operating), Section 13 has met with them concerning various issues, they have their own dragon scale (and in turn have met with Quetzal, and keep tabs on Max and Emmy), have investigated rumors of a strange board game wreaking havoc in New Hampshire, and have also learned of the existence of a small, anthropomorphic mouse living in New York with a human family. However, since most of these assorted phenomena aren't aliens, they normally don't deal with them (though they're still investigating where exactly Dragon Land is- pocket dimension, another planet, floating hidden island even- to determine if that would fall under their purview).

• More credence to the theory is that XGB, MiB and Godzilla all shared an animation style and location (New York). Perhaps if XGB had lasted beyond one season and/or all three shows were on the same network, there could've been frequent crossovers.
• There'd also be a connection to DIC Entertainment's library due to the presence of the DiC-co-produced The Real Ghostbusters. The MIB would also keep tabs on the Chipmunks and Chippettes and the Dinosaucers, they've assisted Chief Quimby and Penny Gadget in dealing with MAD, have investigated rumors of packs of anthropomorphic cats and dogs living in a small East Coast fishing town, M.A.S.K. has met with them regarding various V.E.N.O.M. plots, they've encountered the Street Sharks and Dino Vengers/Extreme Dinosaurs and keep a tab on Dr. Paradigm, they've learned of the existence of several small colorful beings living with a suburban family, they've met Rainbow Brite and keep a tab on Brian, they keep a tab on the DinoSquad, and so on and so forth. Again, most of these assorted phenomena aren't aliens, so they normally don't deal with them.
• Another connection would be to various PBS Kids shows, since Dragon Tales had a brief mention in Episode 4119 of Sesame Street and there were many, many crossovers between Dragon Tales and other PBS Kids shows in promos. The MIB keep tabs on Mister Rogers and Mr. Conductor, they've investigated rumors of four dinosaurs living in a park in the Dallas-Fort Worth area, they've visited Sesame Street and met the residents there, they've managed to visit Cyberspace and met with Digit and Motherboard, and they created the Odd Squad as a branch of the MIB for kids. Once again, most of these assorted phenomena aren't aliens, so they normally don't deal with them.

Jeebs is a symbiote who merged fully with his host

His blobbiness seems really similar to what we see of Troy's hosts. And we know that after 24 hours the host and the symbiote apparently "become one". I don't think anything we know contradicts this, so why not?

There are still non-MIB humans who remember aliens after the Series Finale.

Zed just used the neuralyzer in a world-wide transmission to erase everyone's memories but there might be people who weren't watching it or wore sunglasses.

The events of MIB III still happened but differently

• The events from that film still occurred however instead of that film's Big Bad, it's Alpha. Kay and Jay's father thwarted Alpha's previous operation but Jay's father died when Alpha take him down with him but Alpha actually went into hiding, making people believed he was dead. Ever since then, Kay became overprotective of Jay and developed the animosity towards Alpha to this day.

The Series actually keeps the continuity of the films, just in a way that seems odd

At the end of the events of the first film, Agent K was neuralysed and Agent L was seen to have been recruited as a new field agent. In the show, however, Agent K is still around, Agent J is a good but less experienced field agent, and Agent L is a scientist more than a field agent. Those seem like different continuities, probably intended to be so, but...

The second film establishes Agent J as seeming like a competent Agent but still obsessed with his time as Agent K's trainee. It says that none of his other partners since then have lasted, showing us his current partner being neuralysed shortly after starting the job, presumably to imply that this has happened to other partners in the past but never actually stating that this happened to Agent L.

Agent L is never seen in this film, so while we are probably intended to assume that she was neuralysed into normality again (or worse, killed/missing in action), we have no actual reason to assume she hasn't simply transferred to a role in which she can use her qualifications. Agent J was a beat cop, so he's happy in a field agent role. Agent L was a medical examiner, so she's happy in a scientific position (doing all those things we see her doing in the show) and we didn't see her because she was assigned to something in the field at the same time which needed analyzing. Not surprising, really. Plenty other agents of the Men In Black have other work that they're doing while J or K are solving the main plot.

Then, for the main plot of the second film to be resolved, Agent K is deneuralysed and returns to work. The plot is resolved and Agent K continues as a returned field agent.

That's when the show is happening:

Agent L is around, but as a scientist rather than a field agent. K is around as a very experienced field agent. J is around, and he has enough experience as a field agent that he seemed like a level-headed veteran in the second film, but now we have K to compare him to and he's investigating a large variety of different aliens, his mere couple of years worth of the Men In Black career is shown as still being a relative rookie compared to K.