You could provide in your spousal sponsorship application documentary evidence of any financial support between you and your spouse.......refer to checklist.....7...PROOF OF RELATIONSHIP TO SPONSOR..e....the documentary could be as simple as a one time money transfer to your spouse of any amount.....how much is your decision as IRCC does not specify......you are not required to provide evidence of a monthly financial support.
Note: its not mandatory you provide the documentary evidence of any financial support.....its only an option you could consider including in your application to proof your relationship.