This requires wetting up a Tumblr to pass your Instagram Images to Twitter. The advantage is that you will choose which images from Instagram to send to Twitter.
If
New photo post
This Trigger fires every time you create a new photo post on your public Tumblr blog.
Then
Post a tweet with image
This Action will post a new tweet to your Twitter account with a linked pic.twitter.com image. NOTE: Please adhere to Twitter’s Rules and Terms of Service.
Explore more great ways to automate Twitter and Tumblr (legacy)