I can't give you an excellently cited response, but consider some facts about the situation from what is known in general.

The Japanese government itself did not sanction the attack, it was an attack planned by the army independently. If the attack had gone well, the results the army were expecting would have been to force their government into accepting any conquests as a fait-accompli like with Manchuria. As it didn't go terribly well, and it was a calculated risk to begin with, this was more than enough for the more non-confrontational government to push back against further military adventures.

The Japanese army up until this time was more familiar in dealing with disorganized and under-equipped enemies, where their own organization and cohesion could be brought to bear powerfully. Fighting Chinese warlords, the somewhat disorganized and ill prepared Imperial Russians in the Russo-Japanese war, and the greatly weakened Russian forces in the Russian civil war. In this respect, Khalkhin Gol, which because of it's lack of scale could interpreted as testing the waters, probably was a huge shock to the Japanese military. Enemies which had two decades earlier been in a state of disarray and backwardness were now fielding some of the most advanced mechanized forces in the world, certainly the largest. Where previously the Russian command had been fairly unimaginative and stuck in the past, at Khalkin Gol the Red Army under Zhukov and Shtern was adaptive, very concentrated, and very deliberate.

Khalkin Gol also demonstrated starkly the weaknesses which the Japanese military itself possessed, especially in the type of combat to be expected in further war with the Soviets. Unlike the close combat infantry and naval driven combat in tropical climates throughout Asia Japan was arguably most prepared for, Japan faced logistics driven armored warfare for which there was next to no readiness for. While the Soviets in many ways possessed equally outdated tanks at the time, theirs were far more numerous, and technologically left room for improvement. The BT series fast tanks were shown to be too thinly armored, but in design principle were better suited to the fluid armored warfare of open steppes,long supply chains, and tank vs tank combat. They would later form the basis for the highly successful T-34 tank family, whereas the Japanese army's best tank in Khalkin Gol, the type 95 Ha-go available in far fewer numbers, was more of an up-armoured infantry support light tank. Japanese tanks, small arms, and artillery development had and would continue to tend towards the lighter, infantry centric, and specialist side of things, whereas Soviet arms in general already had a preponderance towards large numbers and heavier armor-centric war. Japanese industry was not ready to produce further tanks and heavy weapons beyond what they put out in Khalkin Gol, as demonstrated by their pretty flat production rates throughout the war, but Soviet industry had already advanced leaps and bounds since the civil war and was every year advancing steadily towards mass war material production. In short, Khalkin Gol was a foretaste of what a massive industrial and pure land war would look like, and in so many ways the Japanese likely could see their industry was not ready for this.

But maybe to say that it intimidated them would be wrong. Perhaps it would be better to say that it changed the calculus of their thinking. When the Japanese high command ultimately settled on their Southern war plan, the critical concern of oil supplies played a large part in their stated reasoning. Japan could not expect to conduct a long term war or remain a strong military power without access to large oil supplies, and given that the Soviet's real proven reserves at the time were as far away as Baku in the Caucasus region, South East Asia was a more readily available and reasonable goal for the Japanese. They were heavily dependent on oil, and if anything was demonstrated by Khalkin Gol, it was that any future land war would require huge logistical resources, and transportation would be a key component. Japan could not rely on the easily sabotaged Trans-Siberian Railroad to launch offensives, it would have need the ability to fuel trucks, another war material they could not outmatch the Soviets in.