Yes, you can chain a target that is immobilized - as long as it is not part of a hard cc.
For example, you can chain an enemy that is immobilized by talons - but you cannot chain an enemy that is immobilized in a skill such as petrify/fossilize.
how about if you smack someone with reach from a lighting destro? pretty sure the answer is no but its been a while since ive played
Scipio Numantia Red guard Nightblade PvP- AD
Scipio Asiaticus Khajiit Nightblade (CRAFTER/DPS) PvE- EP
Altmer Nightblade PvP- EP
Fueoculto Breton Templar (DPS) PvE- EP
Rasoculto Orc Dragon Knight PvP- EP
Caethus Argonian Templar (HEAL) PvE- EP
Vale Oso Nord Sorc (DPS) PvE- AD
Sir-Galahad-the-pure Altmer Sorc (DPS) PvE- EP
Scipionumantine Imperial Templar PvP- EP
Un-bearable Imperial Warden PVP- EP
Vale Bear Altmer Warden PvP- EP
Baits-All-Zergs Argonian Dragon knight PVP- DC
Was just curious because I am theory crafting with a mag warden right now to see if it has a (rare chance) at being trials worthy for sweaty guilds. Obviously no pet since most trials guilds Ive ran with don't like them