It should, but more as a trailer in jet/fighter form.
Yes I'm familiar with Mospeada and how Legioss and Tread only combine in fighter form. The combined form is the biggest draw to me in getting Tread honestly. I had the toynami alpha and betta at one point and the combined form is very bad ass. Unfortunately their Alpha falls apart on its own and I hated it and sold the set. I also had the CM's set at one point but the combined form is so finicky, prompting me to also sell it. I'm hoping for a good sturdy combination from Sentinel. Sentinel's Legioss is by far the best Legioss/Alpha we've gotten. Hoping the same for Beta (though the Toynami Beta was hefty and pretty cool, but it just didn't have an Alpha to match).