To what extent are dimpled pans interchangeable?
There were five dishes mentioned in that post:


Poffertjes
Dutch pancake puffs.
Small, shallow impressions.
Æbleskiver
Danish pancake balls.
Large, deep (half-spherical) impressions.
Takoyaki
Japanese octopus pancake balls.
Small, deep (half-spherical) impressions with a lip around the edge.
Kanom Krok
Thai coconut pancake snack.
Small, (various depths) impressions
Paddu
Indian lentil &amp; rice ?balls?.
Deep impressions (various sizes), w/ matching lid.


I have tried my hand at making Kanom Krok in a poffertjes pan, and it came out well.  I found that they were a bit too oniony for my taste if I added a pinch of green onion to each side, but it worked out well if I only did it to one of the halves.  (don't leave it out, or it's too overwhelmingly sweet).  If the indentations had been deeper, there would have been more batter, and thus it might've needed two pinches of onion.

You simply cannot make æbleskiver or takoyaki on anything that isn't half spherical — you're not simply flipping it over (like poffertjes &amp; paddu) or joining two halves together — you need to roll it as you're making it.  Æbleskiver can end up with a hollow inside them (that you can fill with apples or such), while takoyaki are often made by flooding the whole pan, and then rolling that extra bit from the top into the sphere so it doesn't have as significant of a void.

You could probably make æbleskiver on a takoyaki pan, but the size difference will mean that you make need a different viscosity and heat to properly set the outside while leaving the inside liquid enough to flow back down to seal the sphere.  Takoyaki in an æbleskiver pan might be more difficult — the larger holes might prevent you from cooking the center through properly.

You can use an æbleskiver pan to make poffertjes, but it's a pain.  Basically, you just put a little bit in the bottom of each one, and then flip it.  You'll still get the right sized puff, because the æbleskiver indentations are much larger (typically 7 per pan vs. 19 for roughly the same diameter).  Not only would it be slower from having less indentations, but it's much harder to get in there to flip.  It'd be like using a Dutch oven to make an omelette — it might technically work, but it's really not the right tool for the job.

If you really had to, it'd almost be easier to make poffertjes on a griddle — just use a squeeze bottle so that you can more easily control the size of the puffs.  It'll be a bit different, but it's better than only making 7 per batch.

I wouldn't make poffertjes on a takoyaki pan — you'd have to make really, really tiny ones, or you'd have to fill it so far that I'd have concerns about the middle cooking properly.

As for the paddu — I've never made it, but it seems to me that it could likely be done it any of the deeper indentation pans, provided you had a good way to cover it to let it steam.  It's quite likely that a poffertjes pan would make for too thin of paddu, as you wouldn't get the expected contrast between interior &amp; crust.



So, to summarize (partially assumptions):


Poffertjes pan: kanom krok
Æbleskiver pan: poffertjes (but it'd be a bit of a pain), paddu (if you can lid it)
Takoyaki pan: aebleskiver (but really small, might be a pain), paddu (if you can lid it)
Kanom Krok pan: poffertjes, paddu (if deep enough &amp; can lid it)
Paddu pan: poffertjes (might be a slight pain), Kanom krok
(Griddle): poffertjes (if using a squeeze bottle &amp; thick-ish batter, but they'll be sub-par)