For interior paint, should I go for Jotun, Nippon, or Dulux? Which one is better?

I'm looking for white color.

Easywash able to wipe clean for light stains like squashed bugs on the wall with just a damp tissue.

For "heavy abuse" external factors like crayons, marker pen, pencils, or dark plastic chair scuffed the white wall, I don't think emulsion paint will suffice.

Anything above absolute cheapest 7L RM35 matex will be OK.
Easywash will work fine already.
No need to waste money on paint above minimum standard since your walls are in good condition i presume? The easywash already tick all the core function incl long lasting colour (since the pigment for easywash and higher comes from same mixing machine)

Absolute cheapest matex memang cut corners alot in the base material and pigment so thats why it only come in fixed colours, it is cheap for CSR project.

Many of my neighbours' contractor also use easywash je for my rumaweep. Virusguard nice to have only lah..any soap and frequent 30secs of washing hands well aka sing birthday song in 3 languages will be far more effective to contain spread of virus.

So far the easy wash holds up very well, i painted a bright yellow so if it faded I'd be complaining all over already some contractor have side deal with Jxxxx shop commission I guess. Your use case for internal wall only is a piece of cake for any decent paint (ie easywash and above) series since it already cost 95 for 5L tub.

if you want really easy-to-clean paint choose higher range paint with sheen finish from your preferred brand

i painted both my toilet with Jotun Majestic Perfect Beauty & Care and my room i painted with the cheaper Jotun Easy Clean, the one in toilet is dirt and water resistance now, i can just spray on the wall with sprayer and wipe off the dirt, after a year now it still look new

my room with the cheaper paint still  hold up well, but the matt surface isn't really that easy to clean. imagine you smash a mosquito or cockroach on the wall, some of their remains will trap on the matt surface and need some work to wipe it off, while on a sheen surface you can just use tissue to wipe it clean

do beware if you are hiring others to do the work, dishonest painters might try to cheat you using lower range product or add some powder to increase the volume per bucket so they can get more profit from you

if you DIY, and you are using the higher range product make sure you clean off those dripping paint quickly, i have quite some paint dripping on my toilet tiles and is super difficult to remove even though they have not fully dried

actually most of the sheen finished paint can do that, you can take a look at ICI dulux as well, they have some paint that come with special finish
go to paint shop take the catalogue and view it under the lightning of your house, they have plain white and plain black as well, it is stated in the catalogue

i dont like white with yellow tint or light yellow, i feel like it will make the wall look old and worn-out

one thing to note though, if you are painting sheen/semi-gloss/gloss paint, most likely you will see 2 tone of color, darker color at shady area and brighter color at area exposed to lightning, this is normal as they reflect more light compare to matt, so for matt you will see more consistent color tone between bright and shady area