The answer to this question is simpler than changing the understanding of the event by aligning the date with the start of the overall kingdom. To change the comprehension of "in the 36th year of Asa's reign" to be "in the 36th year of the kingdom of Judah" is too broad a change and forces us to actually delete the Hebrew text. This explanation also denies the same usage of the text string found in other places ie. 2 Ch 15:10,19, 1 Ch 26:31, etc. The context of these statements on the monarch's reign is as the length relates to the king, not the kingdom.
If the overall kingdom length is to be used to explain the "36th year", this would place the event in the 16th year of Asa, which is one year following the national religious reforms. This immediately should make us question that probability. Why? Asa's turning to Ben-Hadad caused the prophetic rebuke from Hanani the Seer leading to Hanani's imprisonment. To suggest Asa was turning from the Lord for the next 25 years runs counter to the spirit of the text.
These events must have taken place toward the end of Asa's reign, after his 35th year and prior to his diseased feet in this 39th year.
Furthermore, Asa's reign enjoyed 10 years of peace (which was from the Lord: 2 Ch 14:6-7) which began at the death of Baasha and the start of the Northern kingdom's civil war and ended in Asa's 35th year (2 Ch 15:19). This was during Omri's rise to power in the Northern Kingdom.
The modern bible translations are known in places to record details that are clearly wrong in the context. We should not fear these errors as they are inevitably due to transcription issues down through the ages and these errors do not compromise God's word as being inerrant and inspired.
It was the transcribing of the text that got it wrong, somewhere down the centuries, which makes this simply a human copyist error. Sceptics like to attack the faith based on transcription mistakes. But these can always be defended.
My research concludes that rendering the Northern Kingdom's king in 2 Chronicles 16:1-6 to be Omri, instead of Baasha, makes sense to the passage: doesn't contradict the chronology of the narrative and fits what we know about Omri. Omri was a builder (1 Kings 16:24) whereas Baasha was no builder. Add to this that Ben-Hadad was at war with Ahab, Omri's son. It therefore makes sense that the war commenced during Omri's time and flowed into that of Ahab. Omri came up to Judah to cut Asa off. Asa bought the alliance with Ben-Hadad who attacked Omri and continued to do so even during Ahab's time.