What I'd do is strengthen your 4 defenders and get a very good goalkeeper.
It is important to have good defenders to soak the pressure as you know how gifted the attackers in PL.
You will also need a very good goalie who can make quality saves, and pray you don't concede too much.
The most important thing is to make sure you can hold and get as much draw as possible.
Get a good playmaker in the centre, get someone who can create chances.
Get fast striker to make sure the chances can be converted into goals.
Get players who are good at shooting from distance.
It's hard to get players from PL because their payroll is very high for just-promoted team.
I would suggest looking at players who are out of contract and get them for free.
I also played Southampton, brought them to PL from L1 in 2 consecutive seasons.
The first season in PL was really, really tough. I conceded a lot, no matter how defensive the tactic is.
Your only hope is preventing losses and get points as much as possible. Make sure you win against promoted teams as well.
Every single point is very precious. You want to stay in the PL so you can get some money for the next season.
Btw, you can have a lot of transfer fund, but in the end it's about preventing your bank into red.
So, try to get cheap players / free transfers and focus on the defense and goalie.
I couldn't give any certain names since it's your second season and it's totally random, even Salomon Kalou was released on free in my save in second season.
But my line-up last time was:
GK - Brian Murphy (bought him very cheap, only 35k and he did decent job), Cheik N'diaye, Alphonse Areola (free on 5th season), get Jack Butland asap, he will be very good.
DC - Jose Fonte, Paul McShane, Peter Ramage, Naim Aarab, and some loan players.
DR - Manuel Ruz, Seamus Coleman (expensive, but very good for long term), Neal Eardley, Nathaniel Clyne
DL - I spent 5m here for Lee Wallace from Birmingham, Danny Fox, sell Dan Harding and Ryan Dickson since they will be useless
MC - Pablo Barros, Xavi Torres, Morgan Schneiderlin, Ismaila N'diaye, Ravel Morrison and some loans + regens.
AML - Adam Lallana, Ivan Perisic (quite expensive, but very good)
AMR - Jason Puncheon, Donal McDermott
FC - Ahmed Soukouna, Febian Brandy, Danny Welbeck (eventually will be listed), Fraizer Campbell (will be listed as well)
That's my players for 4-5-1 tactic, I had them all in second season in PL and finished 11th, third season at 12th, fourth season at 9th, fifth season at 7th. They don't ask for huge salary and they are cheap, can do decent job in PL. If you want good players (good, not excellent), expect to pay at least 40k. Ivan Perisic even already had 43k wage now in my save.