Any thing like these in game?
Greetings @Kefrem !
Short answer: nope.
There used to be something like that Is Lifeblood Spear alive 🩸? but I was told their behavior was changed.
This weapon? I did not find it to this day, but the description says something about life drain.
I used it after I found it because it was my best weapon at that time, and never noticed any syphon-blood effects 
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In that official description only “Cripple” is listed as the only effect.
Marketing verbiage and nothing more.
The short answer is no there isn’t. The longer answer is that there will never be one in this game due to the obnoxious amount of complaints about an overpowered weapon that would come from its introduction.
I believe only a sigil from the Isle of Siptah can heal you when attacking, forgot which one it was.
But weapons nope, sadly not one.
It drains someone’s life, all over the ground. Spills it out as a red liquid when you stab them
Probably one day they make it into game. Then nerf it just like the Lifeblood spear! 
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@prologue1337 I (still - I want to buy it for a loong time, but I am lazy to do so) don’t own IoS, but I use a mod that have a weapon which has lifesteal!
@Jimbo Uh-oh, than it is not that unique in that sense, that a lot of weapons are capable of doing that!
One of the wolf sigils on Siptah gives HP/Stam restoration when you finish off a foe. This one last noticed it does not work if your pet lands the deathblow.
Lifeblood Spear gave passive regen. It is a basically useless amount at the moment.
Everything else is flavour text that this one has found.
if you can use mods, EEWA has some perks that can essentially do this when using a weapon and shield combo.
though that is part of the perks, not inherent to any specific weapon or shield