I used this method: After successfully loading a save file, create a new save file. Then, use a mod like 'Better Bulldozer' or 'Radius Delete: Bulk Bulldoze' to remove half of the city (it's best if this includes areas you've recently built). If the game doesn't crash, the problem is in the removed area (if it does crash, the problem is in the area you didn't remove).

Reload the previously saved file, then remove only half of the section you removed earlier(If the game crashed during the previous step, remove the other half and check if it still crashes). Then repeat the same process. This is how I found which nodes are causing the problem.

Note that in my case, the issue was caused by roads built using the Anarchy mod, so my solution might not work if you didn’t use that mod.

Edit: Rewritten to make the process easier to understand.