Hello! I'm new here, and have a couple of questions regarding homebrew.

Firstly, I've created a homebrew Warlock subclass, and I'm informed I can't share it due to it lacking the required number of class features at the required levels. However, I've given the class the standard array of Warlock features at the standard levels; an expanded spell list, two features a 1st level, a feature at 6th level, a feature at 10th level and a feature at 14th level. Is there anything I might be missing?

Secondly, is there any way of adding optional weapon attributes to a magic item? I've created a homebrew magic weapon which has the ability to change in such a way as to be able to alter the weapon attributes of the item. However, all I'm able to see in terms of modifiers is an option to ignore certain attributes altogether, rather than an option to 'switch them on and off', as it were. Again, is there anything I may have overlooked?

Thank you in advance.

Edit: There are two features at first level, and I think I had gone about creating the expanded spell list the wrong way.

In answer to your first question, please see the General Homebrew FAQ #Ω: (https://www.dndbeyond.com/forums/dungeons-dragons-discussion/homebrew-house-rules/131411-a-homebrewers-how-to-faq). Just expand the spoiler under the General FAQ, scroll to the bottom and expand the spoiler under the that set of questions. Be sure to read the headings in the answer.

As for your second question, temporary effects such as you describe are not supported by DDB. You will have to create different versions of the weapon.

Thanks for your response.

However, I've encountered another issue regarding this subclass; I want to give it a feature which allows a character to use an action to give themselves resistance to a certain type of damage for 1 hour. How might I go about this? I can't see anything in  the 'action' section of the feature properties list that would allow this, and I can't see a way to make it linked to feature options, so I'm not sure what to do.

As I stated before, temporary effects are not supported. (The system has absolutely no idea how long an hour will last before in game.) You could either give them always on resistance, or just list it in plain text and create an Action to track the limited uses. You could create a magic item that would apply the resistance tha the player could equip/unequip to toggle the resistance on and off however.

Ok, thanks for clearing that up. I'll see about creating an action for it.

If you need any help with that Action, you can find answers in the Homebrew Subclasses & Species FAQ #4: (https://www.dndbeyond.com/forums/dungeons-dragons-discussion/homebrew-house-rules/131411-a-homebrewers-how-to-faq), and if you still need help please don’t hesitate to ask.