Unless the Morris twins get the charges dropped entirely, any kind of conviction or plea would likely result in a long NBA suspension.
Silly as the trade demand is, the Phoenix Suns front office likely does not want a repeat of last season's chemistry meltdown and keeping Markieff Morris around against his will could cause just such a reaction. No matter what they say in public, you can bet the Suns would prefer to trade Morris if a reasonable return is available.
But even if they don't trade him, the Suns might not even have Markieff Morris for a significant portion of the season anyway.