Wow thank you so much! I hadn't planned on posting everything here, but if this thread for some reason got really popular I might consider. I would mostly like to direct people to my DeviantArt as well as my Instagram and Twitter accounts where everyone can view my entire collection simply without having to navigate through pages.
People don't post many comments on my work on DA, so this may be the perfect format to answer questions about the Mezo Region :)
The pokemon I posted here are the starters that trainers choose from when they start their journey in Mezo Sur. The trainer is sent by Prof. Myrtle in Bromelia Town to her twin sister (Prof. Laurel) in Sacoya Town, who gives them another starter in Mezo Norte. Similar to how you get the additional Kanto starters in X and Y. Click MEZO under my DA bio if you want to explore the map, I'm not allowed to post links here yet.
I have enjoyed making the regional variants. Tentacool and Tentaquest's helmet designs are more based on conquistadors. Man O' War "jellyfish" are named after caravels like the Spanish and Portuguese sailed in their conquest of the Americas.