The phrase "apply more or less" is correct and usable in written English.
It can be used when discussing the degree or extent to which something should be applied or implemented, often indicating a flexible or approximate approach.
Example: "You can apply more or less pressure depending on the material you are working with."
Alternatives: "use approximately" or "implement to some extent".
You can apply more or less heat.
An additional challenge is represented by climate change, as it will force coastal communities to apply more or less drastic adaptation strategies.
While changes in climate and public health have undoubtedly occurred over recent decades, such changes are likely to apply more or less simultaneously across wide geographical and national regions, respectively, whereas changes in TBE epidemiology show marked spatio-temporal variation and incidence has not in fact increased everywhere.
Depending on the gradient, you may have to apply more or less gas.
Depending upon how sharp you want the lines to be - and how masculine you need to look - apply more or less of the darker colour.
Apply more or less pressure as necessary.
But hopefully the boys enjoyed our time together – they seemed to – and maybe got the impression that people sometimes go to work and sometimes look after children and that this applies more or less equally to mummy and daddy.
Kits could be designed with particular tests in mind – and the reaction mix can be adjusted by applying more or less, without the need or equipment to make-up complex solutions.
Aluminum vehicles will probably therefore rely on alternative assembly techniques, including seam welding (in which a strip of molten metal is applied more or less like glue), adhesives, and mechanical fasteners.
Another characteristic feature, one that was to be much criticized by Chomsky, was its attempt to formulate a set of "discovery procedures"—procedures that could be applied more or less mechanically to texts and could be guaranteed to yield an appropriate phonological and grammatical description of the language of the texts.
Uber's clients all have phones on which they can download apps and credit-card details with which they can pay; its drivers' phones have navigation software; the company has algorithms for pricing and predicting travel time that can be applied more or less anywhere, and can be scaled up from thousands of customers to millions just by buying more computing power in the cloud.
