Both.

For what your doing (beach and trails) I'd say the CX. There are very minor differences, but not much. CX tend to be more aggressive, shorter chain stays and not as much tire clearance. Gearing would be a bit different too.

I have the Gravel 20 and love it. Done some trail and cx on it. Scott produces a great machine!! So my vote is Addict gravel 20!!
Only thing I changed was the saddle, bars and I have a second wheelset for cross.

The only difference between the two Scott bikes is the fork- The gravel fork allows for a bigger tire.
But I was an early adopter and bought an Addict CX before there was an Addict gravel- The CX was still an awesome gravel bike.

I like the looks of the Addict gravel 20 a lot- The Ultegra double is nicer than the SRAM 1X offerings.

As alluded to -
Check the differences between gravel and cx bikes. While Scott makes a great bike, they may not be the best solution in this space.

As a CX racer and bike rider... I would vote gravel for more versatility.
If you are "dabbling" in CX, I do not think you will miss benefits of a race-bred cx bike.

However, with Gravel frames offering more tire clearance, you would have more versatility. Run 28c tires for road, or 33 for cx or larger for gravel.

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