For two sets of parametric lines, like:

t = 0:pi/500:pi;
xt1 = sin(t).cos(10t);
yt1 = sin(t).sin(10t);
zt1 = cos(t);

xt2 = sin(t).cos(12t);
yt2 = sin(t).sin(12t);
zt2 = cos(t);

plot3(xt1,yt1,zt1,xt2,yt2,zt2)

fig2plotly();

We getting just polar coordinates axis:

And message:
Index exceeds the number of array elements (1).
We had trouble parsing the line object.
This trace might not render properly.

More about plot3()
https://www.mathworks.com/help/matlab/ref/plot3.html