Ability to present Onboarding forms based on validations of 2 different field

Summary:

Ability to present Onboarding forms based on validations of 2 different field

Content (required):

We are trying to build Onboarding forms that would be presented/ routed based on some condition.

There are 2 fields

• Flexbase Designation
• Flexbase designation exception

The condition that we will need to set is something like this

If 

               Flexbase designation exception = Flex

               OR

               (Flexbase designation exception IS NULL

               AND 

               Flexbase designation = Flex)

Then 

Flex form to be presented

I am not sure if all these 3 can be combined into a single condition.

I tried creating 2 different transitions for the below conditions

1)           Flexbase designation exception = Flex

2)          Flexbase designation exception IS NULL