I used to like Hallmark Combination effect.
I am sure Dr. Neubauer & few others make a few two speed blades
Kris (2 speed) is a great blade. They made Kris Two speed carbon also (with carbon on one side only). But they made like only 50 of them it seems and stopped.
My all time favorite is a modified Giant Dragon Super Balsa 2. I am pretty sure Kris is a medium size head. GD SuperBalsa 2 is large head offensive but not a two speed blade. I had a friend of mine modify this with adding a layer of of carbon (and a stiff layer of wood on top of that) but on one side only. This was my favorite blade but was stolen. Looks like GD is totally out of business and even if not , they don't have a SuperBalsa 2 available. I had many blades designed similar to this design but not as good as GD SB2
The difficulty with this two speed design (for a combination chopper blade) is isolating the stiffening effect of carbon (or composite) from seeping into the non-carbon side. Looks like a thick layer of Balsa does this the best possible.
I would prefer a 180 mm diameter combo blade but no rubbers are available to fit such a large blade. If you are far away from the table, you don't need very quick hand movements like a close to the table player (who should of course use a compact head blade) and larger the blade area, the more the control & more (reversal) backspin from long pips side (and of course top spin from other side in a combo blade).
I am surprised top defenders (or anyone else) don't use a 180 mm blade. (The manufacturers won't make it if I ask. Tibhar makes a 180 mm toy blade. When I asked Tibhar, Joola & everyone else to make me a 180 mm blade with large rubbers, they sort of laughed in my face & told me to get lost. If Chen Weixing or Ruwen Filus or Gionis Panagiotis had asked for it, it would of course have been ready in 15 minutes). My understanding is that these manufacturers do not want to waste their money cutting special dyes to make the blade plus two rubbers for a low life schmuck like me. Maybe Carsten Neubauer will make me one LOL
Why am I craving for a (combo) 180 mm blade ? The increase in control & backspin (any spin) compared to mid size head 9160 mm) & large head (175 mm) is quite significant & if you goto super-largehead (180 mm diameter) it is even more significant. Given that ITTF is super-obsessed with limiting backspin to the extreme to exterminate defenders, I can use all the backspin I can get especially after that after the moronic Durban Aspect Ratio Regulation of 1998. I tried the Dawei 388 rubber which came in large sheets on the cheap Tibhar toy blade and I am convinced a competition grade 180 mm blade would give astronomically more back spin (top spin).
Would love to see such a blade in the hand of Joo Se Hyuk or Chen Weixing not only for back spin but for their would be devastating forehand topspins
Of course I am going to be ridiculed by glue & booster suckers asking me why not use a tennis size racket then LOL
I should not be saying all this because since there is now no limit to the diameter or thickness of a table-tennis blade & since glue & booster sucker top-spinner dominated ITTF is always to looking for every opportunity to limit back-spin to the max, don't be surprised if you see a proposal in next AGM to limit the diameter & thickness of the blade, claiming that they want to do this to limit the speed to lengthen the rallies.
If I can collect a dime for everytime some opponent claimed that my racket was illegal because it was too thick and too wide, not to mention they can swear that my long pips had been removed from the latest LARC (in the middle of a match or after they lost) I would be a billionaire.
BTW the Butterfly defensive blades with carbon on both sides (closest to outer wood layer) suck to the max. The carbon on topspin side is fine but it is ridiculous to have carbon on chopping side. I can understand if such design is for a compact or mid size blade close to the table hitter from long pip side but definitely counter-sproductive in a largehead balde for an away from the table chopper on long pips side