Use a regular artificial Christmas tree and decorate it with halloween stuff from the dollar store.
Is this what you’re looking for. https://www.hometalk.com/10849000/the-halloween-tree
This one looks amazing and you could just as easily use cut branches
Take your Christmas tree and add Halloween ornaments. Then it will be ready to go for Christmas. We had a fake Christmas tree at work, and someone would change ornaments out for Valentines Day, 4th of July, etc.