The Korx start out evil in DA as well. I think that's working as designed.

Different races begin at different alignments. The Torians, for instance, start out pretty strongly "good." In my last game (as Torians) I took every "evil" choice to get good planets, and they were still on the "good" side when I researched Xeno Ethics.

I think the "starting alignments" in DA are as follows (someone feel free to correct me if I got any wrong)

Good: Altarian, Torian, Iconian, Krynn
Neutral: Terran, Arcean, Thalian, Drath
Evil: Drengin, Korath, Yor, Korx

The Drath?

They're good.

The Korx are like the Mafia. They'll quite happily do business with if they are getting something good back in return. If you refuse, they'll get nasty, and they'll resort to even more extreme methods as time goes on. Tell me how that is anywhere near neutral. They are evil, but in a disguise.

The Yor, on the other hand, seem to be just misguided with a farfetched quest to rid the galaxy of organic life. This is likely due to prejudice and can be changed, making the Yor not entirely evil.

Right, but in terms of the game mechanics, the "disguise" isn't working with the other races. Pure evil sets them at an immediate diplomatic disadvantage with strongly good-aligned races. Doesn't make sense for a trader. If they were neutral they'd be stronger.

Or.... maybe that's the intended design: forcing them to start evil so the player has an uphill climb to the more trader-friendly Neutral position? That's the only way it makes sense to me, and it's still a little odd (IMO).

How's this for a balancing idea: instead of 1-99 ethics spectrum, make the spectrum -20k to 20k, with a "good" alignment at 10k, and "evil" at -10k, with neutral at zero, of course. This way, each ethical event can give +/-x to your ethics score, even if you are already completely good or evil. Translating from the existing score, that means Altarians would start at 10k, Korx would start at -10k, and everyone else would start at various points between.

Using the new scale would allow the cost of declaring alignment to scale directly to your ethical choices. Playing as the Korx, if you take all evil choices it may cost you 15k+ bc to shift to neutral. Playing as the Yor, it would be possible that you would need to pay to get your evil status, especially on smaller maps where you can't get as many ethical events before declaring your choice.

That may be a result of the Precursor civil war. The Dread Lords were the ones that turned the (semi-evil) Yor against their Iconian masters, and the surviving Iconians were helped to escape by the Arnor. I guess Iconians lean towards good due to the Arnor association. Or maybe they drifted to that alignment while fighting the semi-evil Yor. Something like that.

Being a mercenary is a position that requires trust, rather than charm.

Nowadays we may regard mercenaries as "evil" and "guns for hire", but when you take a look throughout Earth history, mercenaries have been far from that. Most of the armies until the 19th century consisted mostly of mercenaries, the fact that you hire them for money is exactly what makes them reliable. If you pay, they provide the service requested.
The Korx may sell you their mother, but the price you have to pay for her hasn't been meantioned. Perhaps they are just honest. "Yes I would sell you my mother if you offered me 1 billion credits". Most modern day humans would be tempted, hell, there are still humans today who sell their children into slavery because they need the money.

The Korx may be willing to do anything if you put enough money on the table, but they won't stab you in the back when it comes to the deal that has been made. This would destroy credibility and no charm can compensate that. Trade itself is the definition of the neutral stance: a cost/benefit comparison -> is it worth making this trade?
This also opens up the theoretical backstab -> is it worth betraying, but all traders know that in the long run, trustworthyness is priceless...

Exactly I see them that way too, otherwise why is it made plain in the back story that the Korx are not well trusted or liked.

As far as those honouring deals is concerned what is important to them is not honouring the deal its plain they have no sense of honour, but rather being seen to honour the deal. If a Korx can use the letter of an agreement to betray the spirit of an agreement they’d do it in a heart beat if there was enough profit to make the risk worthwhile.

In their own society not only is selling your mother considered almost a rite of passage, but any Korax who can’t provide for themselves are looked on with contempt and enslaved, killed out of hand or allowed to starve to death in the street, the background material makes that plain.

The Korax clearly have no sense of honour or empathy, they are purely out for number one and are driven mostly by greed.

Dealing with the Korax I see like making a deal with the devil, check the wording very carefully don’t give them any wiggle room and still you just know they’re going to get the better of you in the end.

Yes you can have honourable traders who people will like to deal with but that’s not the Korax, people don’t deal with the Korax out of like or trust but rather need and greed, things the Korax understand very well, and are very good at exploiting.