I recently tried to homebrew a scythe, no enchantment, it wasn't a blessing, feature, trait, or ability, just a plain scythe, and because I didn't like the idea of a paladin using small sickles I made it a battleaxe variant, it matched the backstory and aesthetic of a character, he believes he is the physical embodiment of death on the earthly plane, but my homebrew was rejected because it wasn't enchanted, I believe the best way to fix this would be to add a section for non-magical homebrew items, like if you want to make a set of brass knuckles for your monk, or a specific style of knife for your rogue, like just something to make un-enchanted custom weapons for your characters that you can share with others.

If you just want to rename and/or make minor tweaks to a weapon, you can already do that. Click on it and then choose Customize in the sidebar.

I know that, but I'm saying if you want to make a weapon that doesn't fall under the category of any weapons there are on here there's no way to make an un-enchanted version of it.

Quote from Stormknight >>

You're welcome to homebrew as many non-magical weapons as you like for private use.

You don't need to submit them for public use. :)

Also, as inquisitivecoder says, you can use an existing standard weapon and just change the name on your character sheet using the customize function.

The Customize function does not even allow you to change the description of an item, merely its cost/value, weight and name. You can add notes, but not remove or change any details, even if it's just fluff text.

I wanted to make a proper gambeson using the stats of  "studded" leather as a more sensible form of light armor, but there's no way to actually do that; I'm still stuck with the item description for "studded" leather regardless.

It is not possible to simply reskin/reflavor an existing item;  the "Customize" function is only for changing weight/cost and giving a name to your specific weapon/armor/etc.

This is true, but I think a non-magical option on homebrew items would still be interesting.

I am now making a dwarf artificer that uses a hammer as weapon and tool, I want her to be able to throw it around since she is strong so I'm using a Warhammer trading Versatile for Thrown (15/30). The problem is that since the homebrew hammer is considered magical (eventhough it doesn't have any enchantments, just some changed properties) I can't apply artificer infusions to it on my sheet since the system recognises it as magical.

Customizing is not the same as creating a homebrew item.

I'd like the ability to create completely new items with different properties and stats, not rename existing items.

I'd like to create a trident that does 3d4 damage, or a new type of firearm for my gunslinger.

These are thinfs that the existing tools dont't allow you to do.

Quote from Balseiro >>

This is true, but I think a non-magical option on homebrew items would still be interesting.

I am now making a dwarf artificer that uses a hammer as weapon and tool, I want her to be able to throw it around since she is strong so I'm using a Warhammer trading Versatile for Thrown (15/30). The problem is that since the homebrew hammer is considered magical (eventhough it doesn't have any enchantments, just some changed properties) I can't apply artificer infusions to it on my sheet since the system recognises it as magical.

 
I ran into a similar problem with the Boomerang that already exists in the system. For some reason they did not give it the Thrown property, so I can't infuse it as a Returning weapon, and I can't create a non-magical version with the property. Quite frustrating.

I'm also having this issue trying to make a smiths hammer that can be thrown and non magical for my artificer. I wish I could add the thrown ability to a mundane warhammer.