If Fox is doing side B at a height lower than roughly the level of the ICs' heads and you're right at the edge, you could try shooting ice blocks. They can function kind of like jabs here, but are able to intercept sweetspotted side-Bs, too, which a lot of technical spacies can do pretty consistently. I don't do this much in this position, though, and there are probably better options if you're looking for a nice, deterministic way of edgeguarding space animals.
A couple miscellaneous things about edgeguarding space animals; if the space animal is recovering low, I like belay OoS -> Nana edgehog and then either charge a smash with Popo or grab once the space animal comes close to the edge; the latter is probably better in theory. I think I talked about this when discussing belay OoS earlier.
Another thing worth throwing out there is edgehogging when space animals recover high. A lot of spacies who up-B high will try to sweetspot the edge. If I think my opponent likes to do this, I stand sort of close to the edge and face it, and then right before the directional part of the up-B starts, turn around and wavedash -> fastfall edgehog. I've gotten a lot of low-ish percentage KOs that way. Plus, once you kill somebody this way, a lot of the time they'll start aiming their up-B such that they land on stage in this position instead, which is easy to punish.
Random thoughts about Falco's lasers:
We all know Choknater's trick of approaching Falco with synched short blizzard when he's laser camping; Popo takes the laser whereas Nana's blizzard gets through, which can be nice for landing unexpected grabs or applying pressure. The downside is you get punished really badly if Falco doesn't shoot a laser when you expect him to.
I think there are a couple better alternatives, although I'm not 100% positive they work since I haven't tested them. The first one is run forward and when Popo gets hit by a laser, have Nana blizzard. This serves a similar purpose as Choknater's trick, but has the nice advantage that you can do it totally on reaction and don't have to worry about getting ***** if Falco doesn't laser, in which case you can do some other attack, shield, retreat, etc. instead.
The other idea is really similar: wavedash at a laser while facing forward and have Nana blizzard when a laser hits Popo. I think this would be a little better than the last option I listed. For one thing, you can do this out of shield, whereas the prior idea isn't viable then. Another thing is that in the prior option, you need to be able dash long enough such that Nana can crouch and then blizzard, whereas there is no such issue here. Also, I think you can send Nana forward a bit if you wavedash very shortly before the laser hits you, whereas Nana will blizzard behind or in roughly the same spot as Popo with the last method.
I still think the first idea could be useful by virtue of it presumably being pretty easy to do on reaction. Or, I could just be forgetting something about Nana's AI that would prevent any of this from working at all. >_<
