The rules of the elemental type suggest you'd be able to. They only suggest however, it's not definitive.
It looks like the major aspects are treated as per wildshape, which is it's self treated like the various polymorph "shape" spells. Along those lines polymorph effects states.
When you cast a polymorph spell that changes you into a creature of the animal, dragon, elemental, magical beast, plant, or vermin type, all of your gear melds into your body. Items that provide constant bonuses and do not need to be activated continue to function while melded in this way (with the exception of armor and shield bonuses, which cease to function). Items that require activation cannot be used while you maintain that form. While in such a form, you cannot cast any spells that require material components (unless you have the Eschew Materials or Natural Spell feat), and can only cast spells with somatic or verbal components if the form you choose has the capability to make such movements or speak, such as a dragon. Other polymorph spells might be subject to this restriction as well, if they change you into a form that is unlike your original form (subject to GM discretion). If your new form does not cause your equipment to meld into your form, the equipment resizes to match your new size.
So, if you're carrying the weapon when you change it will meld with your body and you won't be able to use it. However, I don't see any reason you couldn't drop the weapon first and then pick it back up again or have an ally hang on to your "elemental scimitar" for you to grab when you change.
I would talk to your dm though, they may allow you to "choose" for the weapon to not meld with you when you change so that you don't have to resort to the methods I mention above.