It depends on the company that makes the trailer and how it attaches, but in general the answer is yes, with some modifications.

Most trailers come with a “universal” attachment or hitch (see photos for examples) that attaches to the axle of the rear wheel of your  bicycle.
The axle of your Capri electric rear wheel is M12x1.25, which means it is 12mm in diameter with a thread pitch of 1.25 (1.25mm between each thread).

Most universal attachments are made for axles that are 10mm in diameter, which is a more common size for non-electric rear wheels. There should be no issue in drilling the 10mm hole of the universal hitch wider to 12mm, however, the company that makes the trailer may not recommend this because of liability.

We have done so for one of our staff with zero issues and years of use (see photo for example). You can always try writing to the company that makes the trailer you are interested in to see what they suggest; be sure to let them know you have a bicycle with a
rear hub motor with a solid M12x1.25 axle.

Some companies may make a specific attachment piece for this size axle. What you cannot do with your electric wheel is replace or change the axle, this part is integrated into the hub. Some companies will recommend taking a look at a third party provider like the Robert Axle Project but this is
not a valid solution because you cannot replace the entire axle.

You can replace the axle nut, the part that holds the wheel to the frame, but it must be the same diameter and thread pitch as the axle, which most companies do not stock (they are usually M10x1, which is 10mm). To summarize: Your best option is to modify the "universal Hitch" so that it fits on a 12mm diameter axle (drill the hole wider), or replace the axle nut with one that is compatible with M12x1.25 axle diameter and thread pitch. 

Example of a “universal” hitch or attachment, with a 10 mm hole for the axle.

Example of a  trailer hitch that has been drilled from 10mm to 12mm and installed on an electric rear hub motor behind the axle nut, note the extra washers used so that the axle nut does not turn the hitch when tightened. 

Here are examples of what companies offer to replace the axle nut, in this case you can see there are no options in the correct size of M12x1.25 (⅜ x 26 is close to 10 mm).

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