Most likely you can not. It would be like crossing honey bees and horses. You may get results by related species, but not with different species (e.g donkeys and horses, bees and potentially other insects - I don't know - but no horses and honey bees). Generally when talking cross pollenation you are talking crosses between very closely related plants.

Tomatoes and chillis, quite possibly as they both belong to the same genus - a hot tomato, now that would be interesting!
Olives and chillis? Unlikely, but note I did not say impossible. Those more knowledgeable about the genetic makeup of both might have a better answer.

Sorry, not same genus, same family. The tomato and chili belong to the solanum (often called deadly nightshade) family. They belong to different genera, Lycopersicon and Capsicum respectively.
A better answer to your question would have been - No, but there are always exceptions!

Olives are related to forsithia and lilacs but I do not think they have been cross bred . If you succeed in that let me know . eggplant ,peppers,potatoes, tomatoes,Japenese lanterns tomatillos,narenjilla are all members of the nightshade familly but none have been cross bred with each other.
However the brassica family all crossbreed these include :turnips, kale , rhuatbaga , cabbage, broccoli, cauliflower, rape,mustard,chinese cabbage, brussell sprouts, collards. the only stupid question is the unasked question.