We present the anisotropic clustering of emission line galaxies (ELGs) from the Sloan Digital Sky Survey IV (SDSS-IV) extended Baryon Oscillation Spectroscopic Survey (eBOSS) Data Release 16 (DR16). Our sample is composed of 173,736 ELGs covering an area of 1170 deg$^2$ over the redshift range $0.6 leq z leq 1.1$. We use the Convolution Lagrangian Perturbation Theory in addition to the Gaussian Streaming Redshift-Space Distortions to model the Legendre multipoles of the anisotropic correlation function. We show that the eBOSS ELG correlation function measurement is affected by the contribution of a radial integral constraint that needs to be modelled to avoid biased results. To mitigate the effect from unknown angular systematics, we adopt a modified correlation function estimator that cancels out the angular modes from the clustering. At the effective redshift, $z_{rm eff}=0.85$, including statistical and systematical uncertainties, we measure the linear growth rate of structure $fsigma_8(z_{rm eff}) = 0.35pm0.10$, the Hubble distance $D_H(z_{rm eff})/r_{rm drag} = 19.1^{+1.9}_{-2.1}$ and the comoving angular diameter distance $D_M(z_{rm eff})/r_{rm drag} = 19.9pm1.0$. These results are in agreement with the Fourier space analysis, leading to consensus values of: $fsigma_8(z_{rm eff}) = 0.315pm0.095$, $D_H(z_{rm eff})/r_{rm drag} = 19.6^{+2.2}_{-2.1}$ and $D_M(z_{rm eff})/r_{rm drag} = 19.5pm1.0$, consistent with $Lambda$CDM model predictions with Planck parameters.
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