We are looking forward to your visit or we are looking forward to your visit.

Both are OK. Both "Welcome to come" and "Welcome to come" can be used and have the same meaning. They express the meaning of waiting for guests to arrive. Among them, the word "visit" is generally used in shops, hotels and other places to express welcome to customers; the word "come" is more used in formal occasions, such as meetings, ceremonies, etc., to express respectfully waiting for the arrival of distinguished guests. Therefore, which one to use depends on the occasion and context.