Ok let me break down Xiba's possible strategies:
Keep out: Xiba has the tools to do this. 66B and 44B are good mid pokes that aren't too slow for their range. 33A is a tracking low poke. 1A is a safe sweep which will hit quick steppers. 1B gets Xiba away from the opponent, while being a low poke with decent damage. FC1B is a long range, but probably reactable low poke but it seems to Super TC; it goes under Hilde 22B, which Ceirnan liked to use a lot. 66A is a long range safe tracking mid, but it closes the distance. AAK is a high damage CH tool at a decent range. He might have the strongest range, competing with Siegfried, Asta, and Hilde. BB is ok, earlier I said it was a NC but people just weren't blocking lol. The only thing he seems to lack here is whiff punish. 3BK and 22B are really strong, but outside their range he has 3kB, which does at least 40 damage and knocks down. 3kB also serves as his punisher, probably.
String pressure: 6BK, 6AK, A+BK, AAK, and 3BK are all delayable strings that end in a high kick that stuns on CH, leading to a combo. Some of this stuff might be gimmicky, they are highs after all, but the stopped strings are safe, I think. There's also 22AB, 66K/33K string, 66BBB and his BEs. Sadly 22AAA is gone but he got something to compensate. His damage with these moves is very high. There's some funny properties with the K followups in 6BK and 6AK; he sidesteps before he does the kick and it evades things, sometimes even when the first hit of the string whiffs.
Stance pressure: 3(B), 22A(B), and B(B) cancel the strings into his stance. His stance has fast invisible mixup tools. AK tracks and launches, B does a lot of damage and causes a sit-down stun, and K is a knockdown low. 3B is especially scary because the string followup does a LOT of damage and can clean hit, and if just 3(B) hits it will launch and combo into stance B or K.
Reverse mixup pressure: B+K manually enters the stance and it aGIs horizontals and kicks. Everything else will be steppable. His step whiff punish up close is 22B which combos into BT B+K. 4A and 44K will also beat everything. 4A steps and TCs with a safe-looking high attack, and 44K is a BEable TJ mid kick. 1K and 66A (lol) also TJ. 1B can be used to escape. If they start to hesitate, B+K will give you a free three-way mixup. If they block 4A or 44K, just do it again! Actually I have no idea how safe these moves really are, but everything seemed to be working, even stopping strings into grabs. For after ducking grabs he has WR K which does a lot of damage and can be BE'd for more. WR K is preferred over WR B since idk what to followup with. 3bK maybe? His CE is a counter which beats everything! GG Maxi and Siegfried stance pressure!
Standard up-close mid-low-tracking mixup: For unseeable lows he has the crotch crushers 1A+B and 3A+B, kB, and 2K. For slower and possibly readable lows he has 33A, 1A, and 11B. For tracking he has 6A, 22A, 2A (remember this is a fast 2A), AAK, 44AA, 66A, 1A, 33A. For mids... he doesn't really have any fast safe +on hit mids that I'm aware of. I'm just assuming 1K and 6B are still -frames on hit, and that his stopped strings like 66B, 3A, and 3B aren't both advantage on hit or safe. But you have fear advantage to work with. Other mids are pretty slow but they're there.
You can kinda see how you can seemlessly transition between these strategies with 66A to close in from range, 3(B) as a power mid with stance pressure or string ender on block, and scare them with your reverse mixup and string enders so they just stand and block so you get free up-close mixup, risk free movement, and ranged mixups and guard pressure.
So that's the character, think of him as new and drop your Mina/Kilik strategies. There probably isn't that much more to him.
Edit: Found it! 4A is Kilik's 33A, but faster. and Xiba has Kilik's 4KB too, same input. And he has Kilik 4B and 4(B).