Thanks for writing.
If you both have HSV-1, then you cannot pass it to each other.
Once a person has been exposed to HSV-1, their body will create “antibodies” for HSV-1, which will protect that person from getting it again.
So, since you are your partner both have the same strain, you are protected from getting it/giving it.
In short: you will not trigger an outbreak, and there is no reason to think you can pass HSV-1 between each other. He can give you oral without worrying about passing HSV-1 to you, or getting HSV-1 from you! We wouldn’t recommend worrying about this or having to “look out for” anything!
Hope this helps. Please feel free to submit another question if needed.