Specifically, those who did so on their first playthrough.

That being, do the achievements for beating Normal mode once, "Bush Rescued", and 100%ing it in said mode, "Everything and the Kitchen Sink", stack with their Hardcore counterparts?

Update: Ok, thanks to a Steam user named Frodo Swaggins commenting on a similar discussion I made on Ty 3's page, it turns out they do!:

Originally posted by Frodo Swaggins:

yeah all achievements can be done in a hc run (all ty games). however the final boss in ty 3 is insanely hard if not impossible to normally do in hc. only way to win is to cheese it by using a specific combination of stones for your rang to make you invulnerable while you stand still. forgot what the combo was but you can google it.

Source: https://gtm.steamproxy.vip/app/411980/discussions/0/3810659147966756362/

However, if anybody wants to give me any advice for beating this mode in Ty 2, then feel free to comment below.