what unis should i pick for psychology

All are 'good' Unis so it probably depends on what you want in a Uni environment.
L'pool and Newcastle are city Unis and with all the big city stuff that goes with that- this suits some people and not others. Loughborough is smaller and cosier, and probably a cheaper pace to live. Its also a top Uni for sport (its a training base for Team GB/Olympics etc, and even if you don't intend to get involved at any sort of 'elite' level, it means it has a great big Olympic sized pool and gym etc.
You will probably get invited to Offer Holder visit days in the Spring Term and these are a good opportunity to look around more critical, double check course details and info about placements etc, and talk to current students about what they like about the course/Uni. And remember, you do not have to make this decision for months, and there is no advantage in making this choice early, especially because once you have entered it, you can't change your mind.

I have applied to Bsc Psychology (3 yr) for most courses apart from Loughborough which is a 4yr course with placement year but other unis offer optional placement year which is the same I’m guessing. I’m quite indecisive about my insurance. I am looking for placement year opportunities so I probably would prefer Loughborough or Newcastle even though Liverpool has lower grade requirements. I know placement years are never guaranteed but I prefer the option of having it rather not at all.
My firm: University of Leeds offered - AAB (Access to Leeds - ABB)
Insurance options:
1. ⁠University of Liverpool - BBC
2. ⁠Newcastle University - BBB
3. ⁠Loughborough University - BBB
(all contextual offers)

I’m also unsure whether I should take into consideration that Loughborough isn’t a Russell Group university, despite ranking around 8th for psychology.

Really - it does not matter. RG is just marketing fluff and it doesn't mean anything in the real world. Employers are far more interested in your degree result, any placements etc, and 'interesting person' than 'which Uni'.

Should you take rankings into consideration?