The Soviet Conscripts already have merging and if it was so full of bugs and exploitable why hasn't it been removed until now? If the Soviets have it then somebody else can probably have it as a doctrinal ability, I don't see anything wrong with that.
And they also tried to remove the RNG involved in call in squads, that's why you don't see it with the Osttruppen Reserves and Partisans anymore bringing in shrecks and having varied amount of veterancy (not for those units specifically but it was a thing a long time ago for other Armies and their units).
Yes, conscripts merge is working fine (most of the times, some issue I heard when merging with the reworked assault guards), but introducing a new wehrmacht unit... well... I don't know modding, but looking at the weird bugs that came up for seemingly simple additions is a bit concerning, like look at how broken the royal engineers were, all due to the deconstruct ability.
Yes, rng was for those abilities removed, and I think it's good. What I meant is that one of the two squads would always have AT equipment, while the other one never (or always have AI equipment, like an lmg)