please God just call it port

[TouchandFeel]

They should just go all in and change it to Steorbord and Ladebord.

Honestly, I am surprised how few people have heard of larboard but as someone that loves etymology, I am familiar with a lot of antiquated words and terms.

Anyways, I kind of feel that this was intentional to make the challenge about quick pattern recognition and wouldn't be surprised if they avoided using left/right or port/starboard because they wanted it to be a bit more difficult to parse, but then again that does make it more obfuscated than the implementations in other languages. If they do color-code the words or effects, they definitely need to make starboard green and port/larboard red.

While starboard and larboard are very similar, don't focus on the whole word and just look solely at the beginning letters while ignoring the rest of the word. So instead of thinking "okay it's larboard then starboard", think " okay it's L and then S". It'll make your life a lot easier by filtering out all the similarities that can muddy up your ability to quickly discern them.
Also smart positioning based on the boss is of course necessary. Look at the way he is facing and position yourself accordingly.

As for remembering what sides equates to what, what I use is that star = steer and most people are right-handed and so you steer with your right hand, hence starboard is on the right. The explanation is a bit long, but you get used to it and it gets shortened in your brain quite easily.
Then if star is right, then port is the other side which is left.

EDIT/TLDR:

Sorry for repeating myself but here is a visual explanation of a super easy way to make this not a problem.

Larboard -> L-> Left (the letter even matches up with the direction!)
Starboard -> S -> Right

Basically stop taking in the whole word and making it harder on yourself.