I have a 16 month old female GS who I never played tug with until a recently. When we first started out she seemed to like it but now doesn't want to play at all. The last few times I tried to play anyways, I am using a fleece tug.
She has a super high ball drive even more than food but isn't really interested in a tug.
When we did play she never really pulled very hard and then it dwindled.
With the limited info is there any suggestions that may help me? Or maybe some questions.
There are many times when I take her out for a walk and start to play with her getting her to chase me she goes for my arm. I could easily use a bite sleeve with her at that time and thought of getting one because she seems like she would enjoy that.

first, check her teeth, I've been advised after a certain age the handler NOT to wear a sleeve and decoy their own dog. If here teeth are ok I would use the tug as a prey item, the pro's will jump in pretty soon with more advice, a hungry dog back tied in a harness should help as well

I'm not really planning on a sleeve but it sure would be fun,and
her teeth are fine. If she were even remotely interested in the tug as she is with the ball I would be set.

Will she play tug with a ball on a string?

You could also try putting the tug on the end of a lunge whip (or something similar) to stimulate prey drive via rapid movements. This should make the tug more interesting to her. You could then start the game of tug from a distance (other end of the line) after she has captured the prey.

I think that because she has never played tug before she may just not know how to play. Usually we teach our dogs that when we touch something that they have in their mouth, they need to give it.

So start by letting her win. Build her drive with the tug, when she bites it, let her have it. No tugging at first. Keep her on a leash so you control how far she is away from you, let her walk around holding it, feeling all proud she won it. Don't take it from her, walk her in small circles, when she drops it, she loses it and it is now yours again. Keep doing this for the first few sessions. Then start with small pressure on the tug, and let her win it again.

If she has a lot of drive she will quickly learn the game. Just let her build her confidence by winning this object from you and slowly work your way to an all out tug game. Never just yank it out of her mouth until you are SURE she get the game. When she does, and you yank that thing out when she has a shallow bite or a lopsided bite, she will work twice as hard to get it and not let you have it back.

play tug with another dog. yours will see what fun it is and want to do the same