How long in each region? (OC/Sona Help)

I know I've asked this before but this is a more thought out version of my question.

I have a Trainer OC/Sona from Unova who embarks on her journey at 18 (Replacing Hilbert/Hilda) and her first adventure is the BW1 storyline with the only difference being that her, Cheren, and Bianca are young adults and not 14 year old minors. I do this because I ship her with N (Among others) and pedophilia ain't gonna happen here.

Now that we have that established, my character travels to each of the regions in the main series Pokemon games. For her journey, I'm using Black 1/2 for Unova, Platinum for Sinnoh, SS for Johto/Kanto, Y for Kalos (Fits the story better even as an X girlie), AS for Hoenn (Since it's mostly water anyway), US for Alola, Sword for Galar, Legends: Arceus for Hisui (Obviously), Violet for Paldea, and Legends Z-A to go back to Kalos. While she's in each region, she does everything we as players would like the actual story, gym badges (Or Alola's Island Challenge), Pokemon league, contests (When present), showcases (Taken from the XY anime for Kalos), post game story, etc. I also want to include the canon time skips, like her second time in Unova being two years after the first and her trip to Johto being three years after her Kanto one.

With all of that considered, how long should she spend in each region? I've settled on a year so far but should I go higher? If one year by starting at 18, I'm imagine she'd be 29 by Z-A.