The TVRS-44 Ladoga should be for about 44 passengers (it is also in the name).
The company developing it says that they used the design of the let l610 as a starting point, but it is a different aircraft, and it has also some solutions from the An-72 and from the An-140.
So now it is a fully Russian plane.The TVRS-44 Ladoga is not a foreign type.And it will be manufactured in Russia entirely from russian components.Furthermore it is a high wing aircraft, so it is more adapt for some harsh conditions than the low wing il-114 (which is more rugged than an equivalent western aircraft but is also more delicate than the an-24).
The il-114-300 is for 68 passengers, so it is a larger aircraft and both of them are needed for Russian regional aviation (and possibly for export to friendly countries).
The il-112, like any military cargo can transport troops but it is a different thing than passenger transport.
What I mentioned is that except for vehicle transport, most of the things that an il-112v could transport could be also carried by a Ladoga (which has the same payload), and eventually a rear ramp derivative of the Ladoga could be also done.
Please also take into account that the engines of the An-26 were also less powerful than the engines of the il-112V (2800 hp of takeoff thrust vs 3000 hp (3500 is the emergency max performance)).
You do not need a more powerful engine for a 6 tons payload military transport aircraft.
You need a more powerful engine if you want a larger aircraft with an higher payload (e.g. An-8 or the C-27J (which albeit slightly shorter than the il-112V has a wider cargo area and twice the payload (about 11 tons).
Russia could even think about developing 2 aircrafts, with the same cargo size (except the length).
One with 2 PDV-4000 engines and a max payload of about 10-12 tons and a longer one with 4 PDV-4000 (or two turboprops derived from the PD-
with a max payload of 20-25 tons.
This would be similar to the relationship between An-12 and An-8.
By the way, here some data
C295 cargo area
The lenght of its cargo hold is12.69 m lenght
1.90m cabin height, 2.70 meters max cabin width (actual width Limit for large object 2.23 m)
C27j cargo hold width 3.33m widthby 2.60m heigh
Il112vThe cargo hold is 8.4 m long, 2.45 m wide and 2.42 m high
An 26HOLD SIZE (L X W X H): 11m X 2.22 M width X 1.6 M
DOOR SIZE (W X H): 230 X 167CM
TOTAL LOAD VOLUME: 30 M
Cabin width (m) 2.78
Cabin height (m) 1.91
TVRS-44Cabin width (m) 2.60 (same as An-140)
Cabin height (m) 1.90
No data about potential cargo hold size, but the cabin width is 18 cm narrower than the An-26, so we can expect about 2.04 m width of useful cargo hold
Concluding The TVRS-44 Ladoga is the aircraft derived from the let-610 prototype (with also some parts previously used in the An-140, manufactured in Aviakor in Samara).
It has the same fuselage width than the An-140, so a little bit narrower than the il 112v.
Anyway the TVRS-44 Ladoga can probably substitute the Il-112 in most tasks (and the An140 in everything) and is fully Russian.
Note: the CASA (now airbus) C295 has a longer but narrower cargo hold which is optimised for pallets transportation (and also less powerful engines).
In theory it has a higher max payload than the TVRS-44 or the il-112v.
By the way
There are a lot of silly comparisons online saying that the C295 is much better than the C-27J, but they are most BS.
Some even say that they have the same payload 9tons (they compare the max payload (with overload and gload limitations of the C295 with the max air droppable payload of the C-27J).
Off topic.
Concerning the "foreign" aircrafts from Let, the development of the let- L410 and of the let L610 was paid by Russian (Soviet) money.
Yes there were some soviet alternatives (to the 19 passengers let l410), like the Beriev Be-30 or the Antonov An-28, but they are not in production anymore (Poland is still building a derivative of the latter called PZL M28 Skytruck, with Pratt and Whitney engines).
The Ural Civil aviation plant is instead fully capable of building both the Baikal and the TVRS-44 Ladoga aircraft and in the last 5years has also built let L410 (albeit with a certain amount of imported components).
Thanks to the Baikal there will be a russian engine also for the let-410. What Russia needs is just to do a russian derivative/modernisation of it (like Poland did for the An-28/ PLZM28) and the problem is solved for the 19 passengers sector.
The cargo part will instead be covered by the Baikal (which has similar payload and range).