I’ve never emulated PS3, but FMHY (freemediaheckyeah) is always my go-to starting point for answering this kind of question. They usually have awesome recommendations:

https://fmhy.net/gaming#playstation-roms

You should start by determining how it knows the trial is expired.

Try installing it without internet access to see if it phones home. If it gives an error before installing, (but doesn’t say the trial is expired) it might be phoning home to see if the trial is expired.

If it installs offline and still tells you the trial is expired, then that probably means it left some trace of itself somewhere on your computer.

Once you know which method it uses, you can start to work on bypassing it.

I’m guessing it either stores/modifies a file on your computer to let it know that it’s been installed before, or it might use an online check using some kind of hardware identifier.

If it checks online, Wireshark may help. What operating system are you using?

My rules that haven’t led me astray yet:

• Use Linux
• Use Firefox with uBlock Origin with all/most of the built-in block lists enabled
• Stick to reputable sources listed on FMHY and the r/piracy megathread
• Prefer open source emulators and source ports for gaming
• Have an automatic backup system that does off-site backups
• Use network-wide or system-wide host blocking using custom DNS servers for your router or operating system (such as Pi-hole or NextDNS) with aggressive block lists

while shielding it from legal liability

You think the plan was to take the fall for the company? Why would he do that?

Can you give a few examples of some movies that would fit in this group? Do you just mean movies that were popular in the '90s, like Home Alone (1990), Wayne’s World (1992), Jurassic Park (1993), Forrest Gump (1994), Scream (1996), and The Matrix (1999)?