Does this have any damage multiplier or not?

Creating a character now who will be based around sneak and blade, I'm just wondering if two handed will work with a sneak build?

It can work so long as you're sneaky enough, which is fairly easy to do

That's good to know! Is there still a damage multiplier though?

There is always a chance of a Sneak Critical, unless you use two handed weapons.

However, the Sneak Criticals are not needed really.

From the Wiki:

Blade and Blunt Two-Handed

Advantages:

• Two-handed weapons are more powerful than one-handed weapons.
• Two-handed weapons have a longer reach than one handed weapons.
• The enchantment from a shield can be used without reducing http://www.uesp.net/wiki/Oblivion:Spell_Effectiveness
• Two-handed weapons have more health than one-handed weapons, allowing them to last longer in drawn-out battles.

Disadvantages:

• Although a shield can be equipped to use its enchantments, it cannot be used to http://www.uesp.net/wiki/Oblivion:Block or contribute to your http://www.uesp.net/wiki/Oblivion:Armor_Rating#Armor_Rating.
• Two-handed weapons are more expensive than one-handed weapons.
• Two-handed weapons are generally slower and heavier than one-handed weapons. (There are some exceptions, e.g. http://www.uesp.net/wiki/Oblivion:Akaviri_Dai-Katana)
• Two-handed weapons do not allow you to carry a torch at the same time as your weapon. This can be a problem in dark caves if you do not have spells, potions or enchantments for http://www.uesp.net/wiki/Oblivion:Light or http://www.uesp.net/wiki/Oblivion:Night-Eye.
• If you sneak attack with a two-handed weapon you will not get the sneak attack damage bonus.

I reckon it depends upon how had you want to roleplay, would a sneaky character use a two-handed weapon...?

Thanks CCNA! I think I'll use one handed weapons but keep a two handed with me aswell