Hi @Anonymous ,
Yes you can store any kind of data from one entity to another entity using Power Automate. Here are the steps for you and the screen shot.
Pre- Steps:
1. Create your Entities Organisation A and Organisation B with relevant fields and choose proper field type.
Steps:
1. Create an instant flow -give a name
2. Choose "Common Data services -Current Environment"
3. Choose the trigger "When a record is created or updated" or any thing which relates to what your are trying to do
4. Choose Contact Entity and choose your scope (I have chosen organisation)
5. Add a new step > again choose a "Common Data services -Current Environment"
6. Choose your entity (In your case organisation A) . In my case "Portal Invitation" > Then you can map your field from "Contact Entity steps"
6. Repeat steps 3 to 4 and filter your query then add your customised action to create a record.

Key: Here the beauty is on the first step I have circled the Filter Expression where you can write a simple ODATA query to filter your organisation and create a record to relevant entity.
Hope this gives you some good idea on how you can utilize power Automate with CDS.
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