Japan lacked incentives for this, previous to June 1940. While the war with Chian was not going well short term credit in the US and London banks was still available, trade with the US, British, French, and Dutch empires was relatively open. Tensions were not much worse than a year or two earlier after sinking a US warship and beating up a US diplomat. Economically and politically this makes little sense.
Militarily its a weak move previous to July 40. Italy is neutral & had given Japan no indication it was headed to war with its former allies in Europe. That left a sizable portion of the French and British fleets free to deploy to Asia/Pacfica. Japans own fleet was much weaker than eighteen months later. Its reconditioning and new construction programs were very far from complete. Most of the carrier air arm were obsolescent early 1930s designs. ie: The carrier fighter was the A5M 'Claude', underpowered engine by 1940 standards and just two medium MG. The initial replacement for the A5M was eight to ten months away & full replacement was some 24 months out. The new super battleships were not even launched, let alone shook down and possessing trained crews. Neither was the Army far enough along in its expansion program, having few spare corps or air wings. for operations vs the Brits, French or whomever.
After France collapses the view starts to change. While there are strong economic disincentives to attack anyone, French Indo China did start to look like low hanging fruit, as did the Dutch East Indies. Hence the start of the occupation of FIC in October 1940. The French did not resist because the Germans told them not to, approving or extending permission to Japan. Previously the Franco/German Armistice required France to resist any foreign intrusion into the French colonies. But the Brits were prowling about the globe, Japan was proving a distraction to Germanys enemies, and had little trouble with nazi ideology or objectives.
The results for Japan of the second phase, or escalation of the FIC occupation in the spring of 1941 were a surprise to Japan, and economically devastating. Freezing Japans accounts and activities in the US banks shut Japan out of global trade. So did the disappearance of foreign flagged cargo ships from Japans ports. In 1940 close to half the imports/exports from mainland Japan were on Foreign ships, mostly British controlled. ie: Norwegian, Greek, Dutch, Commonwealth, ect... Cutting off oil imports was almost redundant in that context. Japan could neither pay for or ship in more than token quantities of oil. Ditto for the chemicals, steel & alloys, lumber, ect... japan depended on.