I am not aware that they are much different at least from their shape. Removing the counterweights on an inline-4 crank is in 99% of cases a very bad idea, even more if that engine is supposed to reach higher rpm levels.
AFAIK the k24 cranks are largely the same. The TSX cranks were made in Japan while the others were made in the USA, hence different part numbers.
The TSX cranks were nitride coated.
Here some minor differences are described:
I'm just wondering if there are any differences between the TSX crank and the Accord cranks in the K24s. There is a huge price difference between the two and I need a K24 crank for a stroker motor that I'm building for an S2000. Obviously, I know the stroke is the same for both but I'm curious...
www.k20a.org
Overall I'd say unless you plan to build a monster 600 wHp high rpm Turbo monster engine, I'd not bother.
Higher rpm are not a good idea on a K24 anyhow unless you can life with a lower life span.
I'd also recommend having the rotating bottom end balanced if you intend to rev this k24 rather high.
Weight match all pistons and pins
check con rod balance
have crank, flywheel and pressure plate balanced as a combination.
Then there is a balance shaft set-up integrated in the k24 oil pump. You might want to replace it with a non-balanced shaft equip k20a2 oil pump. That indeed reduces losses a bit, but for the price of higher 2nd harmonic vibrations. The balance shaft set-up is also not that good for high rpm operation.
What rpm limit do you intent to hit?
How do you want to get there?
The cast stock pistons and rods won't like anything near 8k not for a long time.