Boat idles fine, jumps right up on plane, runs about 50 yards WOT and loses power but dosent die or hesitate, just feels like it cuts back to about half throttle. If I push the choke it bogs down more and dosent help. I can let it down to about 1/3 throttle and hold it there for a couple seconds and can feel it regain power then slowly open it back up and around 4800-5000 rpm it cuts back out to about 1/2 throttle or less is what if feels like

Before someone says I'm the OMC guru, I know a lot about them but not all.  It sounds like it's going into the limp home mode and that's usually caused by the VRO or temp sensor.  I've never had one to do this, so I'm not going to start sending you on possible wild goose chases when I know a person on another sight that can help you a whole lot more. 

You will have join the sight but do that and post your question.  Hopefully, a member that goes by the name racer will respond.  He is the guru god of OMC's.https://www.screamandfly.com/forumdisplay.php?20-Technical-Discussion&s=a8ac6f612e24300564e306eaebdc35cc&order=desc

I had a motor use to act like that. Air was getting in the fuel system. Idle great run it wot for a short time would start loosing power

Fuel delivery is a very common cause of this type of problem, however when he presses the primer and it gets worse tells me it's not fuel delivery.  Normally when it's a fuel delivery problem, pressing the primer or hand pumping the primer bulb will make it run better.  

The limp home mode usually cuts it back to approximately 2,500 rpm.  Like I said though, I've never had to trouble shoot or had any dealings with one that was going into the limp home mode, so I'm a little cautious about making recommendations on how to trouble shoot the problem.  

If I had to take the shotgun approach, my first guess would be a heat sensor, but those usually set off and alarm also.  Doing this and not giving an alarm has guessing.

Might try having someone hand pump the primer bulb and see how it responds then.  

Coastguard requires manufactures install anti siphon valves where the fuel line going to the engine connects to the fuel tank.  It's nothing but a barb fitting with a check ball inside.  I've seen several of these fail and make an engine starve for fuel, but that can be detected by hand pumping the primer bulb.  

Also, fuel starvation problems usually cause the engine to surge when held at higher speed settings, not just cut back and maintain a reduced RPM.

He's not pumping the primer bulb he's pushing the key in to choke the engine

10 minutes ago, Hower08 said:

He's not pumping the primer bulb he's pushing the key in to choke the engine

If I understand his system correctly, when he pushes the “choke” he is adding fuel to the mix. If he were starved for fuel or had excessive air I would expect that to  improve the situation. That said I have experienced some pretty crazy stuff when air is getting in where it shouldn’t. Not specifically on an outboard but with dirt bikes. They are different but in large part play by the same rules. 

Hower08, Read what I said in the first line of my last response.  Also understand, that motor does not have a "choke".  When he presses the key in, he's activating a solenoid that opens a diaphragm that lets more fuel go directly into the engine, commonly referred to as the fuel enrichment solenoid.   When you cold start the motor a press the key in, you are priming it, not choking it.

Also read in that response, he could have someone try pumping the primer bulb and see if that held, didn't say anything about he was pumping the primer bulb.  As Ski213 mentioned, two strokes can do strange things, that's why I suggested having someone pump the primer, even though I don't think it's a fuel starvation problem.  That's a quick and easy check.

Although, I guess since I'm just an old retired fart that don't know anything about these things, we can just leave it to your expertise.