Experiences with PSPs and cross-border settlements for niche markets?

Been looking into scaling up our cross-border payment solutions, specifically for less common currencies and regions. The usual suspects handle $EURUSD and $GBPUSD fine, but when it comes to onboarding and reliable payouts for say, parts of Africa or LatAm, the options get slim and the fees jump significantly. Anyone found a PSP or a banking partner that genuinely excels in these more niche corridors without exorbitant spreads or ridiculous KYB friction that delays everything by weeks?