bumping this up just to see if anyone has a guide of what one needs to do to pick this up from HK eShop?
Sure.
First, you need to change your My Nintendo account region to HK, which you probably know how to do already. Just go to my.nintendo.com and in your profile, change country to Hong Kong.
Then, this is the link to the SRWT page in the HK eshop.
超級機器人大戰T 人類前進外宇宙受挫,在衰退與妥協支配的世界中被捲入新的戰爭。 賭上人類和地球存在意義的戰鬥,結果會是……。
store.nintendo.com.hk
Afterwards, click the basket symbol to start with the purchase process.
From this point onwards, you may be redirected to your credit card bank verification system, or the purchase will just go through and a message will appear telling you that a eshop code has been sent to the e-mail associated with the My Nintendo account. Use google translator to see if the message is describing a problem with your card or that you got your game (on one occasion I thought that the message was describing a problem so I restarted the whole thing and bought a game twice, luckily a friend of mine was also interested on it).
The code will probably land on your spam folder, so give it some time (I had to wait some hours the first time).
Now, with the code in your possession, go to your Switch and access the eshop there. Everything will be in Chinese, but you just have to locate the DL code input screen and punch the symbols there to start downloading the game. And that's it.
Don't hesitate to ask and post screenshots if you encounter any problems.