After chatting for a long time, you have called each other brothers. You have a better understanding of his preferences. If possible, you can give him something he likes, because after all, it is the first time you meet, so you don't need to give him something particularly expensive. You two met in the game. Can you give him a gift related to the game? I have a more creative idea, but I don't know what kind of gift you two play. You can customize a pair of real dolls, imitating the characters in your game, and replace them with your avatars. If you think this is not appropriate, just customize the dolls of the two of you standing together.
You can also give him a box of chocolates, the kind that should be customized, and write words like "brothers" on it to let him feel your sincerity. This is very suitable for the occasion when you meet for the first time.
You can also give him a customized necklace. There are many kinds of customized necklaces now, including lucky clover styles, name styles, and tag styles. You can customize one according to your preferences and his preferences and give it to him. He will definitely like it. This kind of necklace is beautiful to wear and is a good choice.
I don't know if my idea is the same as yours, but I still suggest that when you meet for the first time, it is enough to show your sincerity. There is no need for special gifts. Having a meal together is good enough.