I doubt it'll have 2 engines while able to lift 80-120Ts.
Two PD-35 engines would give it 70 tons of thrust.
The An-124 originally carried 120 tons with four 24 ton thrust engines, the An-225 has 6 x 24 ton thrust engines and can carry 250 ton payloads.
The AN -124 has 96 tons thrust, the An-225 has 144 tons thrust.
The Il-106 with 70 tons thrust should easily be able to take 80 tons and with fuel off loaded which it will be designed for 110 tons is the design spec.
With four PD-35s the Slon will have 140 tons of thrust... just 4 tons less than the An-225... of course it will also have two less engines as well which means less weight and drag.
why is it even needed for low rate production?
Because you will be making it out of new materials with new parts with different size on new production equipment... you need to get the design right... hand making them off printed plans is not really an option... the machines that make the parts need digital designs they can't read printed plans...
if nothing else, the FSB can get them. If not, a retired An-22 can be disassembled & drawings made, just like a B-29 was by Tupolev..
Copying an existing example is a nightmare and only a very last resort... plans include information on the material type and hardness of the parts... winging it or guessing leads to issues like Chinese copies of German diesel engines.... you have problems with the wrong materials being used and shattering or wearing out very fast because it is the wrong hardness or the wrong brittleness...
A brand new design would probably be easier because all the calculations have already been made...
they don't need tanks; BMPs, helos, UAVs, trucks & perhaps small bulldozers/excavators r the biggest vehicles they'll have on those missions.
Doesn't matter... an An-124 that can carry 120-150 tons of stuff in one flight is still going to be more use than 3 Il-76s able to take 120 tons, but all their equipment and vehicles are designed to go by Il-76 or Il-76 based aircraft so it all fits... it is just a question of how many aircraft and how many trips they need to take.
The extra width in larger aircraft likely can't be used... the extra half metre or metre or two doesn't allow armour to be carried side by side the difference is not that much...
Once they get Il-106s in service they can redesign their new gear and pallets and vehicles to fit the larger width and get more packed into the bigger spaces, but for now they could use AN-124s anyway.
Furthermore a modern il-106 (or equivalent) will be very interesting for many countries, and a civilian version could also be done (Volga Dnepr would be for sure interested).
But orders of raised from the dead An-22s would cut into export orders for new build Il-106s... which will be quicker and easier and faster to make...
The ideal would have probably been making a 80-90 tons transport plane with a cargo hold width between 5 and 6 metres and powered by two PD35 engines, and a Slon with a wider and longer cargo hold and increased payload (compared to the An124) and range powered by 4 PD35 engines.
Moreover while waiting for the large 35 tons takeoff thrust engines and the finished development of the new project build additional An-124.
Which is the simplest and fastest and most practical solution which is also what they appear to be doing...
the latest I heard & already posted is: they r mulling to modernize/cannibalize those in storage &/ buy some from civ. operators as those have more airframe hours left.
If it was desperate they could build brand new An-124s if they wanted to.... but they clearly don't want to spend that sort of money, which means AN-22s are not even nearly any sort of option... what the lack is that size engine, which is being worked on.
I suspect what will happen is that they will just have a minor shortage of bigger transport aircraft till the new engines are ready and their new planes start entering service.
IMO, some An-12 s could also be modified for the tanker role, like the C-130s were .
The An-12s are old and worn out and about to be replaced.... creating new versions of them now just makes no sense... make some extra Il-276s and develop them as tankers for refuelling front line aircraft... take advantage of its jet engines and higher speed and use it for refuelling Su-25s over the front line at 10,000m... out of range of ground fire...
The problem is that it will only become a matter of time before countries start fitting air to air weapons to their drones to shoot down certain air targets like enemy drones or AWACS or JSTARS or inflight refuelling aircraft and troop transports.