Does power increasing abilities help the opponent?

Question

Does abilities like Technician or Swarm that power up moves power up for the opponent too?

Answer 1

No.

In general, abilities only power up moves of the user.

Hence, Technician of your own Pokemon does not boost the power of the opponent's moves.

The exception to these are field effects brought about by abilities, like Weather or Terrain.

Here is a replay from PS! if you want that as source.

This is what Technician Scizor's Bullet Punch reads as :

whereas Swarm Scizor's Bullet Punch has this description:

Answer 2

no. it will only affect the bearer of the ability unless it specifies it like no guard does.