I actually do switch up my style based on the comic I'm making, and always have. I just think it's fun, but also it helps me get work. It's harder to change the proportions of how you draw, but changing the style of your inking by using different tools or altering the thickness or pen pressure settings, swapping between blackfills, hatching or screentones for shadow rendering, or just changing how you color has a pretty strong impact on the appearance overall. If you can then just tweak the proportions even a little, you're all set.
Errant is drawn in something close to my "default style" or "personal style. It's quite manga-esque in proportions, and very brightly coloured, with bold inks that have the pen pressure set pretty high...
But here are some other things I've done over the years...
Marvel pencil sampler:
Horror short I did with a writer.
Comic concept working on a kids series with established characters:
It doesn't take a lot to change the overall vibe of your work. Change the pen, make it a little grungier... bingo! Honestly one of the most impactful things on what audience people think something is for is the apparent age of the characters. If it's about kids, or the characters are drawn in this wide-eyed, innocent way (like teenage disney characters), people will go "this is for kids".
All that said.... making an entire graphic novel in a style you actually don't like drawing isn't fun. Whether or not you do it should depend on how badly you want to have a big graphic novel drawing gig. When it's just for a while, drawing in a different style can be a lot of fun, but never getting to just draw what you want or in your own style can get fatiguing. It's a big part of why I stopped working full-time as an illustrator and started drawing Errant; the realisation that I hadn't been able to just cut loose and make a weeby comic with bright colours and action about adult characters in years and it was getting me down. I think a big factor in being able to stick out drawing in a different voice for a long time is having the opportunity to also draw in your own outside of that, so you don't feel creatively stifled.