All Tech in under 6 hours help + Do Trophies stack?

[Blasphemous_Bish]

As the title reads, I'm going to attempt the 6-hour trophy soon and have already completed 150 pop during 1st age and 900 prestige in the stone age so any tips would be great.

Both questions have little to no answers anywhere online, hence this post, so a response would be very helpful! Specifically, does completion and hardcore completion stack? If so, that could save a few hours just going through these modes on hardcore instead of standard thus 1 playthrough.

Edited January 16, 2022 by Blasphemous_Bish