Legend 20monk/20sword saint

So first time play through and playing pure human monk (currently lvl 10) on core. Chapter 3 with Aeon currently. I’m thinking about going full 20 Monk with the alt capstone. And then 20 swordsaint. With switching to legend of course… it’s pretty stay intensive with Dex 1st, Wis 2nd, and Int 3rd. I went pummel stance line and piranha strike route. Was interested in opinions and suggestions/ideas from the collective mind. Obviously I’m gonna do whatever I’m gonna do but would love some feedback and hear pros/cons and others insights. Thanks I. Advance.

By monk I hope you mean Sohai (pet and flurry with fauchard for example) or quarterstaff master ( more damage with the stuff and other bonusses when you attack with it).
Sword saint is specialized on one weapon. I am not sure if “monk fist” can be selected for this.

Maybe the instinctual warrior (barbarian archetype) is an alternative to monk. You get the defense bonus of a monk and some monk abilities plus rage and rage abilities. You cannot cast while raging, but sword saint uses spells mostly for buffs anyway.
Main problem for rage classes is, that most players agree that having a skald in your party is better than being a rage class.

So maybe a sword saint 20/monk1/skald19 would be best.
You hit like a truck and buff the whole party.

If you multi class your char should become better in what they can do well already.
Sword saints can hit like a truck, so you should try to make them hit harder.
Monks get a bonus to defense, but they do so at lv1 and then it only gets a bit better. Their unarmed damage increases with lv, but even if you could take it as SS its not a good choice compared to fauchard (reach + high crit chance). Their offensive bonus is flurry but this only works for unarmed and monk weapons (bad choice for SS) and only for full attacks. Many SS go for vital strike which makes flurry useless.
A skald with beast totem line and leathal stance line can give AB, AC, damage and pounce to the whole party, plus some spells, many skills and uncanny dodge.

If you want SS+monk, I would take Sohai with Fauchard. Select a pet with pounce to make as many full attacks as possible. If you want vital strike or cleave then more than one lv of monk is useless.

Else I may suggest SS20, monk1, skald19. This should give you and your party very high hit chance, damage and defence.