My major assets are in SGD. I have seen some posts about negative currency impacts of stashaway portfolios. Which one is better for SGD investors?

I also had the same question recently and came across two fairly new digital wealth management platforms like Endowus and MoneyOwl which allow you to invest in SGD denominated funds.
I recommend reading this very detailed and comprehensive article: https://investmentmoats.com/money/invest-dimens...
It's well worth the time to sit down and read through all of it.
To be fair, StashAway also recently released their SGD income portfolio, however, it isn't globally diversified as it's purely on Singapore listed ETFs.