I hear new growers mention 'shock' a lot. You won't hear experienced growers worrying about 'shock'. I'm not sure where it comes from or if it's just some natural motherly instinct for us to think this is an issue. I'm pretty sure there is no such thing in a botanical sense. Except maybe in the botanic sense of 'oh my god I f'ed up my plants again'. That's a shock I went through as a newbie oh so many times and still sometimes do.
But you can definitely just switch the light cycle. It's what thousands and thousands of growers do every day. It's not like it's going to hurt the plant if you start trying to improve on that method by tweaking things more, but it's not really going to improve upon it, and it's extra work.