That sounds really overwhelming, to be honest. Why not connect with just one or two people a day, rather than message all of them at once? That way, you'll be more likely to keep in contact, because you won't get burnt out or buried under texts.
Also, I would totally encourage you to not judge yourself for needing personal time and space, even if that means not messaging back right away. It's okay to take time to think about your response. A well thought out response will lead to closer more authentic communication and friendship than a generic word or two that was all you could send because you were really tired or lost track of time or felt pressured to respond promptly. Anyone who values you will understand your desire to give their words the attention they deserve.
Anyway, this is just my perspective as another introvert, so if it doesn't work for you, that's okay, too!
Thank you @tessaragabrielle for your insight!
I know it sounds overwhelming but, in fact, it is not. I don't have that many relationships that I want to actually revive. There were some toxic and uninterested people in my chat inbox that I am fine with letting go. Also, I am not planning to text those that I want all at once. I am spreading it over several days to avoid being overwhelmed, as you put it :)
Thank you for your thoughtful advice to not judge myself. I am highly skilled in that area, so it is always nice to get more encouragement from others. You are absolutely right, it is important to have personal space and my closest friends are on the same page as me in that aspect. I always try to avoid responding generically in two-words because I want to support my friends, not just stay in touch.
Thanks for your comment, always lovely to meet another introvert and share opinions. Hope your methods work for you as well :-)