The only risk is that you’ll fill up your mods folder with poses and spend all your time taking photos. Just be careful of downloading from creators who hide their stuff behind adfly - that site can expose your computer to some nasty viruses. Once you do it a few times, it gets much easier and you have a feel for how it goes. I’d try to find some YouTube tutorials so you can watch someone do it.
When I first started, it used a lot of my sim’s time to perfect everything and move everyone around. Since I wanted pictures of every family, I made a spin-off save that I used just for photos. If you put all your photos in a room and save it to your gallery, the photos can move between saves. Totally not a necessary step, but I found it took pressure off me to not need to worry about the game clock, and I don’t need to do that anymore since I have the hang of it.
Ts4-poses on tumblr is an incredible resources. Their master list sorts all the tags so you can find specific types of poses. As you’re getting started, I’d first look at what kinds of photos you want to take and download just a few poses that will get you what you want; it’s really easy to download more than you’ll use.
I’d also look at ravasheen’s iso camera and photo overhaul mods since you want to take portraits in-game. You can set up that camera on a tripod or other surface in front of your posing sims. Then your posing sims can take the picture themselves instead of needing an extra sim to take the photo. The other advantage is her photo overhaul mods get rid of the white mat around your photos.