Can you play Half-Life 2 mods on Half-Life 2 Episodes One or Two and vice versa? Thread

So yeah I surfed the net and can't seems to find any answers to those questions. Like can I play a Half-Life 2 mods on Half Life 2 Episode Two since it's the latest installment and contains a lot of similiar contents? Or does it categorized as a whole different games? If that's so then do I have to have three games installed (HL2, HL2 eps. one and eps. two) in my pc if I want to play let's say three mods from each games instead of playing it all only from Half-Life 2 eps. Two since it's the latest game? Would anybody kindly give me the answer? Thank you in advance.