I was wondering where to find these items

Persoa Blade
Persoa Lance

i cant rmb the rest will post at the bottom when i rmb these are the ones which im really looking for pls help XD

I JUZ RMB MORE ATHENA GEM and ATROPOS GEM where do i get em?

Persoa's Blade: Chest in Yuidora Mine - Beshtora Seal.
Persoa's Lance: Chest in Yuidora Mine - Strange Cavern.

Athena Gem is a map reward on the Emilita Route. Garden Ruins - Mausoleum.
Atropos Gem is a map reward on the Yuela Route. Yuidora Mine - Hidden Passage. And it's a treasure on Yuidora Mine - Hinaos Hall (NG+).

How bout lachesis gem? cuz i wan make an ultimate wep n i need it

Lachesis Gem: Map reward in Yuidora Mine - Secret Seal (Yuela & Serawi routes only).

Yea thx i found it juz a few more things where can i find athena gem and what is the fastest way to level up my weapon mastery to M?

Athena Gem was answered a few posts above.
Weapon mastery is gained by using any attacks (basically everything except defending and healing), independent of whether you kill or simply fight, so go to the location with highest monster density. I can suggest Siege Grounds in Yuidora Mine, Troll Lair in Dijenel Borderland, and Demonic Banquet in NG+ Yuidora Mine, depending on what level you are.

I have another question im now on serawi's route n im on like my 3-4 playthrough but i dont seem to see her ultimate weapon i cant craft it so i was wondering if im missing something i see yuela's but i also dont see emlita's wat must i do to unlock them?

Yuela's, Serawi's and Emelita's ultimate weapons require you to level their last personal weapon - Cutting Moon, Kinolas Retel, and Queen Staff respectively.
Serawi's/Emelita's personal weapons require being on their route (for the 1st one), or leveling up the previous one (for 2nd-4th).
BTW, same applies to the angel maids' ultimates.

but i leveled up serawi's 3rd bow already and im not seeing a 4th anywhere? must i be in a curtain chapter? and for emilita i didnt even see her 1st one wen i played her...(i only played emlita's route once)

Recipes for Serawi/Emi's 1st weapons appear soon after you enter their route (i.e. around chapter 4). Maybe you just missed Emi's.

another quicky where do i find w.eushelly's artifact i know it is valkryie falls but i juz dk where cuz the mobs already dropped their artifax unless one of em drops 2

If you mean "regular" Eushully (the pink one), her artifact drops from Valkyries.