Formal:
* Aloha kākou. (This is the most common and versatile way to say "we love" in a general sense.)
Informal:
* Mahalo nui loa kākou. (This translates to "Thank you very much, all of us" and can be used to express love and gratitude.)
* Ke aloha nei kākou. (This is a more specific way to say "we are loving" and emphasizes the feeling of love.)
You can also use the word aloha by itself to express love and affection, which is a very common practice in Hawaiian culture.