[orpheline]

My personal favorite is an Elecom left-handed model:

ELECOM M-XT4DRBK Wireless Trackball mouse for Left-Handed, EX-G series L size 2.4GHz 6 buttons Black https://www.amazon.com/dp/B016QCPRBM/ref=cm_sw_r_cp_apa_i_0j...

I've got one at work, one at home: very comfortable and intuitive to use.