One of the many mysteries surrounding The Walking Dead season 10 is what the purpose is of the Soviet Union satellite that crash-landed in the season premiere - but it's possible that it will ultimately set up the Commonwealth as well as Maggie's return. Last season, Lauren Cohan exited The Walking Dead as Maggie in the same episode that Andrew Lincoln made his last appearance as Rick Grimes. Maggie's absence was attributed to her working with Georgie on building a new community.
Cohan is slated to return as Maggie in The Walking Dead season 11 - and perhaps even before that in a smaller role - and that return has already been somewhat hinted at. It was mentioned that the Coalition, a name given to the combined communities in the series, hasn't been able to make contact with Maggie in the months since season 9's ending. But now it's possible that her inevitable return to the fold can be connected to the mysterious satellite that dropped out of the sky.
After putting out the fire caused by the satellite, Eugene convinced Michonne to allow him to strip it for parts. Since season 9, Eugene and Gabriel have been working on a radio, one that can be amplified with the right equipment. Using the satellite, the radio can be used to contact communities farther out, including the Commonwealth as well as the community Maggie is with because eventually, Maggie's story will have to intersect with the Commonwealth.
For a long time now, The Walking Dead comic fans have been looking forward to when the Commonwealth will be introduced. So far, the creative team behind the franchise has been skirting around the community by introducing new organizations, such as the Pioneers from Fear the Walking Dead and the CRM group that took Rick. But it's the Commonwealth that will be the ultimate opposition in the end. And their introduction happens thanks to Eugene (in the comics) contacting them using the radio, which is built to communicate over long distances.
So the satellite may result in a domino effect, as is the case with many things on The Walking Dead. Eugene can upgrade the radio using Soviet equipment, which will lead to Maggie's return (potentially once she discovers the Whisperer threat) and then eventually the Commonwealth's introduction. When all of this happens remains to be seen, but if the series continues to follow the general trajectory of the comics, it shouldn't be too long. Perhaps towards the end of The Walking Dead season 10 so that season 11 can being anew.