Spark plug questions for a p0302 code

[ShowMeUrOsFace]

Hey y'all!

2005 Legacy gt 2.5L ~155,000 miles

I am changing our my spark plugs and I bought NGK Platinums because I read on here they're fine if your engine doesn't come OE with iridium and I didn't know the turbo charged to come with iridium. Will putting these in my engine cause problems?! I'm doing this not only cause I think the last owner hadn't changed em in a while but also because I got a p0302 and p000 on my dash code reader. But I took I it to O'Reillys, autozone, and my mechanic whole all only read the p0302. This is my first step into fixing this issue. Slightly rough idle at times can't feel any misfire while driving, but semi evident when stopped (redlight, parked, etc.). My two grounds were corroded and I made some homemade ones to replace them, if there's more ground connections that you know of for me to check let me know.

Thanks

[WRX USA]

This can also be related to a bad coil pack. You could easily swap the coil pack from cylinder #2 to any other cylinder and see if the misfire follows.

[ShowMeUrOsFace]

I've done that already came back same code

[relative4]

Swap injectors next.