I believe that is defined by the compilerOptions.module property of your tsconfig.json file. It compiles your modules differently based on which option you have selected. Try setting it to "CommonJS". Docs here
It may also be in conjunction with the compilerOptions.target property as well. Try targeting "ES5". You may have to play around with different combinations.
compilerOptions.moduleproperty of your tsconfig.json file. It compiles your modules differently based on which option you have selected. Try setting it to "CommonJS". Docs herecompilerOptions.targetproperty as well. Try targeting "ES5". You may have to play around with different combinations.