2012 Kia Sedona 3.5L with 6 speed Automatic, just did this and I'll post some links and paste the most prominent paragraph as you may not want to read my other ramblings;
The transmission fluid exchange.
Some of the guidance I used were found here, scroll down for the links;
Kia Sorento Maintenance - "Most are for the 3.5L V6 and some are for the 2.4L 4 cylinder. In addition, the 3.5L V6 used in our Sorentos has also been used in some Hyundai Santa Fe models as well as some Kia Sedona models and so some videos may be for those vehicles but still apply to our Sorentos."
Here's the post where I found the basic instructions on how to fill the transmission. I opted to fill at the 'check plug' point too, from above with the funnel;
Fill plug was a 24mm plug so I didn't have to use the vent, I just funneled a 3/8 tube into it, then took off the expected outlet line the one to the right as you face the motor/trans, had a connector from
Dorman 030-496 kit to connect it, then after spilling some fluid had to plug the trans end with an orange ear plug, the line leaked also as I ran the motor but the bigger volume was coming out the connection as expected and hoped... I have an ear plug example in the picture. Use the long handle curved needle nose pliers to get the clamp backed off worked great just had to position it a little more toward the access point, the wires present pushed aside easily for access point to remove the clamp and I didn't remove the battery as others reported doing.
I'll add the last photo where I claim to have 'captured it all' for those who like me want it all including the punch-line for brevity's sake...the fluid in the tube was just short of being clean so I had to step out and get another jug of trans fluid at that point, fairly generous room to work in, basically, you're looking toward the side of the battery box and under it, the pliers is a long handle curved needle nose;
And the last short rambling of a new (used) Kia owner who is so far happy and enthusiastic about said purchase;
"you can just see the ear plug that is in the transmission inlet line in-between the right of the pliers and where the white connector is. The red is the funnel and tube. Basically this is the whole set-up, that simple with the drain plug at the bottom, also a 24mm."