The phrase "a much stronger effect" is correct and usable in written English.
It can be used when comparing the intensity or impact of one thing over another.
Example: "The new marketing strategy has a much stronger effect on customer engagement than the previous one."
Alternatives: "a significantly greater impact" or "a far more powerful influence."
However, hedge length had a much stronger effect on bird richness than organic farmland management.
The same quantity of drugs or alcohol has a much stronger effect than it does in adults.
This effect was considerably overridden by Tanshinone IIA treatment with a much stronger effect observed in the early treatment group.
However, seagrasses had a much stronger effect on the macrofauna communities than lugworms, and competitively excluded lugworms.
My analyses of maximum and minimum T2m support a much stronger effect of DLR on T2m at nighttime than at daytime (not shown).
Increasing prawn density decreased periphyton biomass (dry matter, ash free dry matter, chlorophyll a) by 3 6% whereas tilapia produced a much stronger effect.
In contrast, the targeted destruction of highly connected patches had a much stronger effect on the fragmentation of the network than the random removal of habitat patches.
Exchange of cysteines within the conserved CxxCxxC motif has a much stronger effect on cluster formation and stoichiometry than the exchange of a coordinating external cysteine.
Heat release is found to have a much stronger effect in the round jet than in the previously studied planar mixing layer.
As opposed to air temperature at the ground surface, temperature gradient had a much stronger effect on the odour dispersion domain.
Crack has a much stronger effect on the body than nitrous oxide, and so perhaps that is where the "hippy crack" term has some legitimacy: you could say that balloons are like crack for soft-hearted drug takers.
