The most likely outcome is they'd have received the names of 'smaller' stations instead, such as Dundalk, Drogheda, etc. As mentioned by John, naming them after figures either side of the civil war would not be wise politically.
And this would be unwise, it is, after all, a rail transport network, people from every corner of the country would be coming to and from Dublin. Dublin as a whole was quite pro-treaty. Far better to avoid it altogether.
My personal thoughts are if the naming of stations was to be continued after executed leaders of the Rising, it'd likely be famous Irish figures in literature, art, sport etc. Or if you want to embrace our industrial heritage, name it after notable figures of the railway. Broadstone Cusack, anyone? This would have to be taken with great consideration also, of course, as many of the railway companies discriminated against Catholics being in the higher ranks before independence.