I'm looking for manga with a pair of siblings that are brother and sister as main characters with close to equal importance/focus in the story. No preference on what the story is about and can be any genre, though I'm hoping for something that has the two of them working together towards some sort of goal.

I do not want any kind of story that has them paired romantically. Thanks in advance!

Watari-kun no xx ga Houkai Sunzen - I'm not sure if you're looking for the same age or not because here the brother is roughly 10 years older but is pretty much raising his younger sister. The focus is more on the brother, but the little sister is a critical part of the story and definitely not a side character. Together they're trying to tend a garden in their backyard after their original garden was destroyed years ago by a former friend.

Koudaike no Hitobito has stories about the problems that three telepathic siblings face, along with a few other side stories of people related to them. It's mostly comedic with romance in it.

At Each Other's Throats -- A wacky slice-of-life comedy with no particular plot. Both siblings are of equal importance and there's no incest. Furou Kyoudai is similar, but opinion is divided on whether it has incestuous vibes or not. Nothing overt, though.

Fuku o Kiru Nara Konna Fuu ni -- Same as AEOT above, minus the wackiness.

Innocent (SAKAMOTO Shinichi) + Innocent Rouge, with the brother being more prominent in the former and the sister in the latter.

Possibly Perfect Classroom, though with only one chapter out so far, it's difficult to be certain.

Shuumatsu no Laughter should fit quite well. Kimetsu no Yaiba's somewhat similar, but the sister's not that prominent compared to the brother. I dropped this early on, though, so perhaps she gets more focus later on.

Tenkuu Shinpan's also like KnY, but with the sister being the protagonist. Still, I think the brother is at least the deuteragonist here.

Route 225 is a good one.

Tsuzuki wa Mata Ashita, though unfortunately it's been dropped by the scanlators.

Furou Kyoudai
Ran to Haiiro no Sekai

Thank you all so much for the suggestions, I really appreciate it! I'm going to take a look at all of these very soon.