What i understood is you want to send previous value of 'Status' field in the email notification when an item updates.
1. I think you created a new list 'Transaction Log' which will store 'Id' and 'Status'. In this case, when ever item updates in the main list, run workflow like
- Using 'Set Variable' action get the 'Status' value when Id = current item id.
- 'Set a Condition' action, if value of set variable (status) is empty (only first time when no item present in 'Transaction Log History' list with same Id) then 'Create Item' in 'Transaction Log' list with 'Id' and 'Status' fields. Else use 'Update Item' action and update item in 'Transaction Log' with 'Status' when Id = current item id.
- Send value of set variable (status) in 'Send Notification' action.
2. No need to maintain separate list, create a new column called 'Previous Status' in the main list and whenever item updates update the status value in 'Previous Status'. Send value of 'Previous Status' in 'Send Notification' action.
First time alone you will get empty value (when item creation) from second time onward you will get previous status correctly.
I thought of a second status column too as supposed. Just make sure you don't show the new column in your form and hide it from all views to (softly) prevent manipulation by the user.