@r_swift ,
(a) once you have become a resident of the USA, your worldwide income comes under US tax system ;
(b) under US tax laws , the place where you work determines the sourcing of the income - thus if your work is performed in the USA but for a foreign entity with no presence in the USA, your income would generally be classed as US sourced/connected income and therefore taxed in the USA - not eligible for foreign earned income exclusion;
(c) Income earned as self-employed from a foreign entity while living in the USA ( even if deposited into a foreign account in local currency ) and taxed by the foreign country , generally would not be eligible for foreign tax credit ( because the income is NOT foreign ) -- to rectify this situation, one has to resource the income to "foreign" ( asserting US-foreign country tax treaty conditions ) to be able to recognize the foreign tax and credit thereon. It is complicated and therefore generally services of tax professional familiar with international tax laws is recommended
(d) in your particular situation, since Canada generally works on a "resident" basis for income taxation, perhaps you do not need to file a Canada return for the period that you were not a resident of Canada
Hope this answers your query, generally.
For more detailed answer I would need your days present in the USA during 2017, 2018 and 2019 plus the date on which you were admitted into the USA as a resident ( Green Card). Also are you married to a US citizen or a Canadian citizen?
