The heel-to-toe offset in cross-trainers can vary pretty greatly, but generally, 2mm-8mm is the norm for these shoes.
0mm — New Balance Minimus
2mm — Under Armour TriBase Reign
4mm — Nike Metcon, NOBULL, Reebok Nano
6mm — Inov-8 F-Lite G 300
8mm — Under Armour HOVR Rise