To keep this from being a guessing game please post what the weights are of the boat and weight and type of tow vehicle. If you're wanting to tow a 26ft offshore boat with a Subaru it aint gonna work.
For the little bit I pull my boat, I was thinking I was going to be able to make this work. For the long hauls, I still have my ol' truck ... simply letting my 16 yr old drive her.
2014 Jeep Grand Cherokee (little bigger than a Subaru)
Max towing: 6,200 pounds
Max payload: 1,270 pounds
Curb weight: 4,875 pounds
GVWR: 6,500 pounds
GAWR Rear: 3,700 pounds
21' Fish & Ski with outboard on tandem axle trailer: 3900 lbs with gear (little smaller than 26' offshore)
The Jeep Owners Manuals states that a Weight Distribution Hitch is mandatory if towing over 3500lbs.
We have a Jeep GC as well. From memory our max tow is 7,000#+. Ours has the 5.7 V8. I have never towed anything more than a utility trailer behind it. Besides the GoDevil, I have 21ft NauticStar CC with a 150 Yamaha. Probably comparable to your fish&ski. I've never weighed it but I believe the Jeep would pull it well on local trips. I've moved the NauticStar around the neighborhood behind the GC and it looks OK...not much squat. I've only pulled the bigger boat with a pick up truck.
Are the weights you're quoting from a scale or Jeep literature? I would weigh the Jeep on a CAT scale with the front and rear axles on different pads. Check your tires for max payload and max air pressure. Air the tires to max. Hook up the boat and go back to the same scale, they will charge a reduced rate if you re-weigh within 12 or 24 hours after the first weigh. Put the Jeep axles on separate scale pads like before and the boat trailer axles on another. Do the math. Be sure you are under tire capacity and not over the rear axle weight rating. If you put 10% on the tongue (400#) you should be OK.
I'm particular about towing weights and payloads. We have a 12,500# 5th wheel and a 4,000# cabover camper. I have a glove box full of scale weigh slips of the campers empty, with water, heavily loaded, etc.
Please post back what you are weighing and how the numbers work.
edit add....I checked our GC tag...RAWR is 3700, max tow 7,200 (4x4), max tongue weight is 720. 4x2 is 7400 and 740.
I don't see how you couldn't be anything but good. I would hook it up and see if it squats too much. You should be well under tongue weight. For short trips I wouldn't hassle with a weight distribution hitch.