Cookies, it is advisable to use Savoiardi.
Brandy can be replaced with other strong alcohol or liqueur. You can do without it at all.
Coffee is better to cook natural, strong.
About cream – this is such a General dispute. Tiramisu was originally invented with egg whites. But now you can often find cream. Someone is afraid to eat raw eggs. Some people think that cream tastes richer. In any case, it’s up to you. If you prefer egg whites, instead of the specified amount of cream, whisk 4 egg whites to stiff peaks. Mix coffee with brandy. Pour into a wide bowl and let cool.