https://youtu.be/xYm-rSCmG9k
Here is a video of my large breed puppy being introduced to my adultYorkie. At this point in time the puppy weighed almost 3x Razzles weight.
Note the controlled environment - the crates and the two adults in the room. Note the continued petting and loving going on between the two dogs and the stoppage of too rough play. Note how we introduced first our own home and ourselves to that puppy. It was late at night when we picked her up from the airport - if it was daytime she would have been introduced to our backyard first.
Male female intros are usually quite easy - males know a female when they smell them. Males are usually hard wired to accept females.
So in essence keep the environment small and controlled show equal loving to both dogs - and then see how they get on.