Since you already got the answer for XLM as an undervalued coin, I would like to suggest coins like ADA, XRP, SC, FUN fair etc tokens which are really picking up these days very fast. I have come across these coins through various invest program and staking programs which led me to understand how these projects are still undervalued and carry bigger potential. Nonetheless they are having utility purpose which can make them more brighter in the near future. Some of them are based on locking of the funds and thus creates market demand naturally giving more value to it as the minting slows down for the supply. I think many coin are out there to choose from. Every person loves different coin and invest in them. Many people may not like my coins, and vice versa. So its always good idea to keep researching on your own choices and make that difference.