Psh - "timeline without Hitler" - amateurs.

Every society that finally gets time travel suddenly turn into baby murdering monsters.

Here's an example of how an experienced time travel society handles the Hitler problem in a timeline:

We went in when he was just starting to be committed to his struggling art career and promoted the heck out of his shitty work to a Jewish art dealer with a single daughter, who in turn became his patron.

With a little matchmaking, he ended up falling in love with the daughter, eventually even converting to Judaism to marry her.

Their family didn't have the easiest time with the rising antisemitism in Europe, and he ended up arrested at a protest for Jewish rights and spent some time in prison.

While in prison, he wrote the book Mein Kampf, a book about the struggles of being a Jewish family in Europe in the early 20th century. While not the best written book, its plain language resonated with a lot of people and changed many hearts and minds regarding tolerance and inclusivity. It's since been published in several dozen languages and is a frequent citation for civil rights leaders in that timeline.

Anyone can kill a baby. But it takes a skilled hand to guide towards better outcomes.

(Just check in every so often to make sure he never gets political power - that always ends badly no matter what path you've put him on.)