A homebrew subclass I added has martial weapon proficiency, but it does not appear on the character sheet and does not apply when equipping weapons. The same happens with using Intelligence as the ability score for magic weapons, as the Battle Smith can.

Link: https://www.dndbeyond.com/classes/artificer/subclass/450040/edit

What do you want us to do about it?

You should contact the author of the homebrew.

I am the author of the homebrew. I'm trying to get some assistance from the mods to figure out why the system isn't working.

I'm going to take a stab in the dark and say the system is working fine, you've just not set the feature properly.

A system issue would affect everyone, which is not the case because I just tested this and was able to grant my test sorc proficiency with all martial weapons.

Modifier Type: Proficiency
Modifier Sub-Type: Martial Weapons

That will allow the homebrew thing to grant proficiency with all martial weapons. Did you use this modifier?

That is exactly how I have it set up. Its currently part of a feature that gives other benefits as well, but I've tried moving to be its own separate feature and it still does not function. I more or less copied the set up directly from the Battle Smith subclass, which is working fine for me.

Quote from NCRanger22 >>

That is exactly how I have it set up. Its currently part of a feature that gives other benefits as well, but I've tried moving to be its own separate feature and it still does not function. I more or less copied the set up directly from the Battle Smith subclass, which is working fine for me.

 
Even more of an example of why it's something you have done. Possibly something else is causing a conflict.

I cannot access the subclass to see how you've set it, you can either list all the modifiers used in the subclass or wait for a mod.

Additional info: I used my wife's account on another device to create a character using this subclasa, and everything works fine. This seems to only be happening when I make a character using it.

There have been reports of some homebrew not working properly on accounts where the new character sheet framework is active.  You can find out if an account is using the alpha of the new sheet by clicking on the arrow next to the character name (on your sheet), choosing Preferences, and scrolling all the way down.  If it says something like Version 3.0.0-alpha.62, you are on the alpha.  If it doesn't, you aren't.  So maybe you are and your wife isn't?

If you can post a link to your affected character sheet, that may help the developers track it down.

Thanks, I am on the new framework. That's what I figured the issue was.

Character sheet link: https://www.dndbeyond.com/profile/NCRanger22/characters/27769077

Hello, I am able to see Martial Weapon proficiency on the provided character. There are no magical weapons equipped to the character, which is required for the modifier you describe (from the Battle Smith Artificer). If you equip a piece of magical weaponry, do you see the Intelligence effect?

Everything seems to be working now!