Logically, the risk is the same for seasonal and "live" characters. Botting is botting, and the risk of being banned is always there. However, I personally tend to stay away from trying to bot my seasonal characters early in the season, it looks too suspicious to me for someone to jump to the top that normally only plays a few hours a day.
However, if you've already gone "botting crazy" and you're already flagged, it's only a matter of time anyway. I don't bot 24/7, and I almost always monitor my bot when it's running (nosy and chatty clanmates), and I've never been touched. Yet, at some point, I will probably face the banhammer too.
Others have said Blizz doesn't really care about non-seasonal, but none of us really know for sure.
The advice the mods and admin have given all along has been: If you truly don't want to lose your account, don't bot.