Somewhat related to this question, I can\'t seem to find an \'in-framework\' way to change the rotational axis for an A-Frame object (like Earth\'s tilted axis, for example).
I think you can add an additional parent entity around everything and rotate that.
<a-entity> <!-- Grandparent entity -->
<a-animation
attribute="rotation"
easing="linear"
dur="60000"
to="0 360 0"
repeat="indefinite">
</a-animation>
<a-entity rotation="0 0 25"> <!-- Parent entity -->
<a-box position="0 0 0></a-box> <!-- Child entity -->
</a-entity>
</a-entity>
Open the A-Frame Inspector (ctrl + alt + i) and play with the rotation to see which way you want to rotate.