To install you'll need OpenIV (Links down below)

INSTALLATION:

1. Go to "mods/update.rpf/x64/levels/gta5".
2. Drag n' drop the "popgroups.ymt".
3. Go to "mods/update.rpf/common/data/ai".
4. Drag n' drop the "ambientpedmodelsets.meta".
5. Save and enjoy!

If you already have a edited popgroups.ymt or ambientpedmodelsets.meta, simply search up "a_m_y_beach_04", "a_f_y_beach_02", or "a_m_o_beach_02". Without the quotations of course. And copy and paste the contents in whatever section it is in. For example, "Ocean_General" in the popgroups.

Areas that you'll find the peds in are: Vespucci Beach, Del Perro Beach/Pier, Pacific Bluffs, Paleto Cove and beach area, and can be found either on sunlougers or sitting next to a pool.

OPTIONAL FILE:

This file tweaks their walkstyles and what radio stations they listen to.
I also edited both the Music Locker bouncers and Cayo Perico guards.

1. Go to "mods/update/x64/dlcpacks/mpheist4/dlc.rpf/common/data".
2. Drag n' drop the "peds.meta".
3. To see it worked, change your player model to one of the peds. A trainer like Menyoo or Simple Trainer will work.
4. If it did, you succeeded!

LINKS:
OpenIV: https://www.gta5-mods.com/tools/openiv
Menyoo: https://www.gta5-mods.com/scripts/menyoo-pc-sp
Simple Trainer: https://www.gta5-mods.com/scripts/simple-trainer-for-gtav