Torben,
You can choose which "experience" you would like to use when you are in the tool. You can use the "old" experience with Dialog nodes, or the "new" experience with Actions. When using the API, you can use both the V1 and the V2 API with your Watson Assistant instance. You just need to decide how you would rather use API.
So to answer the original question, it is possible to deploy a "old" version of your bot, and then create asecond "new" version of your bot as a second assistant. They would be deployed to different endpoints - but both could be deployed from the same Watson Assistant instance on the IBM Cloud.
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Daniel Toczala
Community Leader and Customer Success Manager - Watson
dtoczala@us.ibm.com------------------------------