Yes and no. Depends on what you consider an arrest. Colloquially, yes, any law enforcement can arrest you for any level of offense. Technically, the arrest is made by the officer with jurisdiction that you end up being transferred into their custody and putting their name on the paperwork. The big bottleneck here is that the Feds decline to have many people held because they don't have enough people to take the transfer. They perfer to let the state level law do their work for them (as on many topics they're basically the same). In the case we're talking about, the Feds generally don't care about marijuana in a traffic stop since their policy is to basically ignore it in states where it's legal.

You can call it detention as well, but colloquially arrest is when you're taken into police custody.

Enforcement begins whenever someone is detained and federal LEOs routinely request assistance from local LEOs... and they get that collaboration.