Try to design a pair of bevel gears, one of which is eccentric. This is the simplest pair of "non-circular gears", if you learn how to do this, you can design non-circular bevel gears of various geometric shapes.
Gear ratio (average) 1:3, all dimensions are free.
The gears should look like the attached image, there is no need to design a mathematically correct gear profile.
I didn't use equations to build models (I used SW tools) but if you need it you can use.
If you need hints 3d models are in my profile. The motion of working gear pair also in my profile, unfortunatly i couldn't upload it here.
Have a good time!)